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Takehara M, Kyakuno M, Okamoto K, Tazawa I, Furuno N, Furumitsu M, Ukena K, Imamura T, Takeuchi T, Hayashi T. Amphibian newts as experimental models for studying weight gain after castration. Endocr J 2024; 71:181-191. [PMID: 38220202 DOI: 10.1507/endocrj.ej23-0207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2024] Open
Abstract
Vertebrate animals often exhibit sexual dimorphism in body shape. In mammals, decreases in sex hormones caused by testicular castration can affect body shape and occasionally lead to pathologies such as obesity. Post-castration obesity can also be problematic for the health of companion animals, including non-mammals. In order to understand the mechanism of post-castration obesity in vertebrates other than mammals, experimental models are required. We examined whether the Iberian ribbed newt, which has recently become a popular experimental model for amphibian research, could serve as a model for analyzing changes in body shape after castration. In newts, new testes can be regenerated after removal of differentiated testes. We analyzed changes in body shape by removing the testes under conditions in which they could regenerate or conditions in which they could not regenerate. Removal of the testes reduced blood testosterone levels. The body weight and abdominal girth of the newts were increased compared with normal male newts. Transcriptome analysis of the liver showed that a set of genes related to lipid metabolism was continuously up-regulated in castrated newts. Our study suggests that changes in body shape after castration are common in vertebrates. Iberian ribbed newts are thus a suitable model for comparative studies of the long-term physiologic- and endocrine-level effects of castration.
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Affiliation(s)
- Mai Takehara
- Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima 739-8526, Japan
- Amphibian Research Center, Hiroshima University, Hiroshima 739-8526, Japan
| | - Mitsuki Kyakuno
- Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima 739-8526, Japan
- Amphibian Research Center, Hiroshima University, Hiroshima 739-8526, Japan
- Faculty of Life and Environmental Sciences, Shimane University, Shimane 690-8504, Japan
| | - Kazuko Okamoto
- Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima 739-8526, Japan
- Amphibian Research Center, Hiroshima University, Hiroshima 739-8526, Japan
| | - Ichiro Tazawa
- Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima 739-8526, Japan
- Amphibian Research Center, Hiroshima University, Hiroshima 739-8526, Japan
| | - Nobuaki Furuno
- Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima 739-8526, Japan
- Amphibian Research Center, Hiroshima University, Hiroshima 739-8526, Japan
| | - Megumi Furumitsu
- Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima 739-8526, Japan
| | - Kazuyoshi Ukena
- Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima 739-8526, Japan
| | - Takuya Imamura
- Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima 739-8526, Japan
| | - Takashi Takeuchi
- Division of Developmental Biology, School of Life Sciences, Faculty of Medicine, Tottori University, Tottori 683-8503, Japan
| | - Toshinori Hayashi
- Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima 739-8526, Japan
- Amphibian Research Center, Hiroshima University, Hiroshima 739-8526, Japan
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Kato M, Iwakoshi-Ukena E, Narimatsu Y, Furumitsu M, Ukena K. Expression of mRNAs Encoding Hypothalamic Small Proteins, Neurosecretory Protein GL and Neurosecretory Protein GM, in the Japanese Quail, Coturnix japonica. Zoolog Sci 2024; 41:50-59. [PMID: 38587517 DOI: 10.2108/zs230070] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Accepted: 11/13/2023] [Indexed: 04/09/2024]
Abstract
Neurosecretory protein GL (NPGL) and neurosecretory protein GM (NPGM) are novel neuropeptides that have been discovered in the hypothalamic infundibulum of chickens. NPGL and NPGM play important roles in lipid metabolism in juvenile chickens. The physiological functions of NPGL and NPGM in sexually mature birds remain unknown. The Japanese quail (Coturnix japonica) seems to be an appropriate model for analyzing NPGL and NPGM during sexual maturity. However, studies on NPGL or NPGM have yet to be reported in the Japanese quail. In the present study, we identified cDNAs encoding precursor proteins of NPGL and NPGM in the quail hypothalamus. In situ hybridization revealed that NPGL mRNA-expressing cells in the hypothalamus were localized in the infundibular nucleus and median eminence, and NPGM mRNA-expressing cells were only found in the mammillary nucleus. Immunohistochemistry revealed that NPGM-like immunoreactive cells were distributed in the mammillary nucleus, whereas NPGL-like immunoreactive cells were not detected in the hypothalamus. Real-time PCR analysis indicated that the expression of NPGL mRNA was higher in the hypothalamus of females than in that of males, and NPGM mRNA expression showed no sex differences. NPGL and NPGM mRNA expression in males was upregulated after 24 h of food deprivation. In females, only NPGM mRNA expression was increased by fasting. These results suggest that the physiological functions of NPGL and NPGM are different in quail, and these factors are involved in sex differences in energy metabolism.
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Affiliation(s)
- Masaki Kato
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan
| | - Eiko Iwakoshi-Ukena
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan,
| | - Yuki Narimatsu
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan
| | - Megumi Furumitsu
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan
| | - Kazuyoshi Ukena
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan,
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Narimatsu Y, Kato M, Iwakoshi-Ukena E, Moriwaki S, Ogasawara A, Furumitsu M, Ukena K. Neurosecretory Protein GM-Expressing Neurons Participate in Lipid Storage and Inflammation in Newly Developed Cre Driver Male Mice. Biomedicines 2023; 11:3230. [PMID: 38137451 PMCID: PMC10740756 DOI: 10.3390/biomedicines11123230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 12/04/2023] [Accepted: 12/04/2023] [Indexed: 12/24/2023] Open
Abstract
Obesity induces inflammation in the hypothalamus and adipose tissue, resulting in metabolic disorders. A novel hypothalamic neuropeptide, neurosecretory protein GM (NPGM), was previously identified in the hypothalamus of vertebrates. While NPGM plays an important role in lipid metabolism in chicks, its metabolic regulatory effects in mammals remain unclear. In this study, a novel Cre driver line, NPGM-Cre, was generated for cell-specific manipulation. Cre-dependent overexpression of Npgm led to fat accumulation without increased food consumption in male NPGM-Cre mice. Chemogenetic activation of NPGM neurons in the hypothalamus acutely promoted feeding behavior and chronically resulted in a transient increase in body mass gain. Furthermore, the ablated NPGM neurons exhibited a tendency to be glucose intolerant, with infiltration of proinflammatory macrophages into the adipose tissue. These results suggest that NPGM neurons may regulate lipid storage and inflammatory responses, thereby maintaining glucose homeostasis.
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Affiliation(s)
- Yuki Narimatsu
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan (E.I.-U.); (S.M.)
| | | | | | | | | | | | - Kazuyoshi Ukena
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan (E.I.-U.); (S.M.)
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Narimatsu Y, Matsuura D, Iwakoshi-Ukena E, Furumitsu M, Ukena K. Neurosecretory Protein GL Promotes Normotopic Fat Accumulation in Male ICR Mice. Int J Mol Sci 2022; 23:ijms23126488. [PMID: 35742932 PMCID: PMC9223635 DOI: 10.3390/ijms23126488] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 06/08/2022] [Accepted: 06/08/2022] [Indexed: 11/16/2022] Open
Abstract
Neurosecretory protein GL (NPGL) is a small secretory protein identified in the hypothalamus of birds and mammals. We recently reported that NPGL exerts obesogenic effects in obesity-prone C57BL6/J mice. However, whether NPGL elicits adiposity in different mouse strains is poorly understood. In this study, we generated transgenic mice overexpressing Npgl using the ICR strain (Npgl Tg mice) to elucidate the obesogenic effects of NPGL in different strains. Npgl Tg mice showed increased white adipose tissue (WAT) mass. Although the mass of brown adipose tissue (BAT) was slightly altered in Npgl Tg mice, hypertrophy of lipid droplets was also observed in BAT. In contrast, fat accumulation was not induced in the liver, with the upregulation of mRNAs related to hepatic lipolysis. These results support the hypothesis that NPGL causes obesity in several strains and species. This report highlights the pivotal role of NPGL in fat accumulation in adipose tissues and contributes to the elucidation of the biological mechanisms underlying obesity and metabolic diseases in heterogeneous populations.
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Kato M, Iwakoshi-Ukena E, Narimatsu Y, Furumitsu M, Ukena K. Effect of Stressors on the mRNA Expressions of Neurosecretory Protein GL and Neurosecretory Protein GM in Chicks. Front Physiol 2022; 13:860912. [PMID: 35370775 PMCID: PMC8964992 DOI: 10.3389/fphys.2022.860912] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 02/24/2022] [Indexed: 11/13/2022] Open
Abstract
We recently discovered novel cDNAs encoding the precursors of two small secretory proteins, neurosecretory protein GL (NPGL) and neurosecretory protein GM (NPGM), in the mediobasal hypothalamus (MBH) of chickens. In addition, we found colocalization of NPGL, NPGM, and histidine decarboxylase (HDC; histamine-producing enzyme) in same neurons of the medial mammillary nucleus of the hypothalamus. In this study, we elucidated the effect of several stresses, including food deprivation, environmental heat, inflammation, and social isolation, on the mRNA expression of NPGL, NPGM, and HDC in chicks using real-time PCR. Food deprivation for 24 h increased NPGM mRNA expression in the MBH. On the other hand, an environmental temperature of 37°C for 24 h did not affect their mRNA expression. Six hours after intraperitoneal injection of lipopolysaccharide, an inducer of inflammation, the mRNA expression of NPGM, but not that of NPGL and HDC increased. Social isolation for 3 h induced an increase in the mRNA expression of NPGL, NPGM, and HDC. These results indicate that NPGM, but not NPGL or HDC, may participate in several physiological responses to stress in chicks.
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Naito M, Iwakoshi-Ukena E, Moriwaki S, Narimatsu Y, Kato M, Furumitsu M, Miyamoto Y, Esumi S, Ukena K. Immunohistochemical Analysis of Neurotransmitters in Neurosecretory Protein GL-Producing Neurons of the Mouse Hypothalamus. Biomedicines 2022; 10:biomedicines10020454. [PMID: 35203663 PMCID: PMC8962320 DOI: 10.3390/biomedicines10020454] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 02/10/2022] [Accepted: 02/11/2022] [Indexed: 01/03/2023] Open
Abstract
We recently discovered a novel neuropeptide of 80 amino acid residues: neurosecretory protein GL (NPGL), in the hypothalamus of birds and rodents. NPGL is localized in the lateral posterior part of the arcuate nucleus (ArcLP), and it enhances feeding behavior and fat accumulation in mice. Various neurotransmitters, such as catecholamine, glutamate, and γ-aminobutyric acid (GABA), produced in the hypothalamus are also involved in energy metabolism. The colocalization of neurotransmitters and NPGL in neurons of the ArcLP leads to the elucidation of the regulatory mechanism of NPGL neurons. In this study, we performed double immunofluorescence staining to elucidate the relationship between NPGL and neurotransmitters in mice. The present study revealed that NPGL neurons did not co-express tyrosine hydroxylase as a marker of catecholaminergic neurons and vesicular glutamate transporter-2 as a marker of glutamatergic neurons. In contrast, NPGL neurons co-produced glutamate decarboxylase 67, a marker for GABAergic neurons. In addition, approximately 50% of NPGL neurons were identical to GABAergic neurons. These results suggest that some functions of NPGL neurons may be related to those of GABA. This study provides insights into the neural network of NPGL neurons that regulate energy homeostasis, including feeding behavior and fat accumulation.
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Affiliation(s)
- Mana Naito
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima 739-8521, Japan; (M.N.); (E.I.-U.); (S.M.); (Y.N.); (M.K.); (M.F.)
| | - Eiko Iwakoshi-Ukena
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima 739-8521, Japan; (M.N.); (E.I.-U.); (S.M.); (Y.N.); (M.K.); (M.F.)
| | - Shogo Moriwaki
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima 739-8521, Japan; (M.N.); (E.I.-U.); (S.M.); (Y.N.); (M.K.); (M.F.)
| | - Yuki Narimatsu
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima 739-8521, Japan; (M.N.); (E.I.-U.); (S.M.); (Y.N.); (M.K.); (M.F.)
| | - Masaki Kato
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima 739-8521, Japan; (M.N.); (E.I.-U.); (S.M.); (Y.N.); (M.K.); (M.F.)
| | - Megumi Furumitsu
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima 739-8521, Japan; (M.N.); (E.I.-U.); (S.M.); (Y.N.); (M.K.); (M.F.)
| | - Yuta Miyamoto
- Department of Anatomy and Neurobiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto 860-8556, Japan; (Y.M.); (S.E.)
| | - Shigeyuki Esumi
- Department of Anatomy and Neurobiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto 860-8556, Japan; (Y.M.); (S.E.)
| | - Kazuyoshi Ukena
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima 739-8521, Japan; (M.N.); (E.I.-U.); (S.M.); (Y.N.); (M.K.); (M.F.)
- Correspondence:
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Narimatsu Y, Iwakoshi-Ukena E, Naito M, Moriwaki S, Furumitsu M, Ukena K. Neurosecretory Protein GL Accelerates Liver Steatosis in Mice Fed Medium-Fat/Medium-Fructose Diet. Int J Mol Sci 2022; 23:ijms23042071. [PMID: 35216187 PMCID: PMC8876799 DOI: 10.3390/ijms23042071] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 02/10/2022] [Accepted: 02/10/2022] [Indexed: 02/01/2023] Open
Abstract
Sugar consumption can readily lead to obesity and metabolic diseases such as liver steatosis. We previously demonstrated that a novel hypothalamic neuropeptide, neurosecretory protein GL (NPGL), promotes fat accumulation due to the ingestion of sugar by rats. However, differences in lipogenic efficiency of sugar types by NPGL remain unclear. The present study aimed to elucidate the obesogenic effects of NPGL on mice fed different sugars (i.e., sucrose or fructose). We overexpressed the NPGL-precursor gene (Npgl) in the hypothalamus of mice fed a medium-fat/medium-sucrose diet (MFSD) or a medium-fat/medium-fructose diet (MFFD). Food intake and body mass were measured for 28 days. Body composition and mRNA expression of lipid metabolic factors were measured at the endpoint. Npgl overexpression potently increased body mass with fat accumulation in the white adipose tissue of mice fed MFFD, although it did not markedly affect food intake. In contrast, we observed profound fat deposition in the livers of mice fed MFFD but not MFSD. In the liver, the mRNA expression of glucose and lipid metabolic factors was affected in mice fed MFFD. Hence, NPGL induced liver steatosis in mice fed a fructose-rich diet.
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Narimatsu Y, Iwakoshi-Ukena E, Fukumura K, Shikano K, Furumitsu M, Morishita M, Bentley GE, Kriegsfeld LJ, Ukena K. Hypothalamic Overexpression of Neurosecretory Protein GL Leads to Obesity in Male C57BL/6J Mice. Neuroendocrinology 2022; 112:606-620. [PMID: 34384081 DOI: 10.1159/000518969] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 08/05/2021] [Indexed: 11/19/2022]
Abstract
INTRODUCTION The mechanisms underlying obesity are not fully understood, necessitating the creation of novel animal models for the investigation of metabolic disorders. We have previously found that neurosecretory protein GL (NPGL), a newly identified hypothalamic neuropeptide, is involved in feeding behavior and fat accumulation in rats. However, the impact of NPGL on obesity remains unclear in any animal model. The present investigation sought to elucidate whether NPGL causes obesity in the obesity-prone mouse strain C57BL/6J. METHODS We overexpressed the NPGL-precursor gene (Npgl) in the hypothalamus using adeno-associated virus in male C57BL/6J mice fed normal chow (NC) or a high-calorie diet (HCD). After 9 weeks of Npgl overexpression, we measured adipose tissues, muscle, and several organ masses in addition to food intake and body mass. To assess the effects of Npgl overexpression on peripheral tissues, we analyzed mRNA expression of lipid metabolism-related genes by quantitative RT-PCR. Whole body energy consumption was assessed using an O2/CO2 metabolism measurement before an apparent increase in body mass. RESULTS Npgl overexpression increased food intake, body mass, adipose tissues and liver masses, and food efficiency under both NC and HCD, resulting in obesity observable within 8 weeks. Furthermore, we observed fat accumulation in adipose tissues and liver. Additionally, mRNA expression of lipid metabolism-related factors was increased in white adipose tissue and the liver after Npgl overexpression. Npgl overexpression inhibited energy expenditure during a dark period. CONCLUSION Taken together, the present study suggests that NPGL can act as an obesogenic factor that acts within a short period of time in mice. As a result, this Npgl overexpression-induced obesity can be widely applied to study the etiology of obesity from genes to behavior.
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Affiliation(s)
- Yuki Narimatsu
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
| | - Eiko Iwakoshi-Ukena
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
| | - Keisuke Fukumura
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
| | - Kenshiro Shikano
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
- Department of Neurophysiology, Faculty of Medicine, Oita University, Oita, Japan
| | - Megumi Furumitsu
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
| | - Masahiro Morishita
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
| | - George E Bentley
- Department of Integrative Biology and the Helen Wills Neuroscience Institute, University of California, Berkeley, California, USA
| | - Lance J Kriegsfeld
- Department of Psychology, Integrative Biology, and the Helen Wills Neuroscience Institute, University of California, Berkeley, California, USA
| | - Kazuyoshi Ukena
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
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Kato M, Iwakoshi-Ukena E, Furumitsu M, Ukena K. A Novel Hypothalamic Factor, Neurosecretory Protein GM, Causes Fat Deposition in Chicks. Front Physiol 2021; 12:747473. [PMID: 34759838 PMCID: PMC8573243 DOI: 10.3389/fphys.2021.747473] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 10/04/2021] [Indexed: 12/25/2022] Open
Abstract
We recently discovered a novel cDNA encoding the precursor of a small secretory protein, neurosecretory protein GM (NPGM), in the mediobasal hypothalamus of chickens. Although our previous study showed that subcutaneous infusion of NPGM for 6 days increased body mass in chicks, the chronic effect of intracerebroventricular (i.c.v.) infusion of NPGM remains unknown. In this study, we performed i.c.v. administration of NPGM in eight-day-old layer chicks using osmotic pumps for 2 weeks. In the results, chronic i.c.v. infusion of NPGM significantly increased body mass, water intake, and the mass of abdominal and gizzard fat in chicks, whereas NPGM did not affect food intake, liver and muscle masses, or blood glucose concentration. Morphological analyses using Oil Red O and hematoxylin-eosin stainings revealed that fat accumulation occurred in both the liver and gizzard fat after NPGM infusion. The real-time PCR analysis showed that NPGM decreased the mRNA expression of peroxisome proliferator-activated receptor α, a lipolytic factor in the liver. These results indicate that NPGM may participate in fat storage in chicks.
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Affiliation(s)
- Masaki Kato
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
| | - Eiko Iwakoshi-Ukena
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
| | - Megumi Furumitsu
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
| | - Kazuyoshi Ukena
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
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Fukumura K, Shikano K, Narimatsu Y, Iwakoshi-Ukena E, Furumitsu M, Naito M, Ukena K. Effects of neurosecretory protein GL on food intake and fat accumulation under different dietary nutrient compositions in rats. Biosci Biotechnol Biochem 2021; 85:1514-1520. [PMID: 33851987 DOI: 10.1093/bbb/zbab064] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 04/05/2021] [Indexed: 12/18/2022]
Abstract
We recently identified a novel hypothalamic small protein, named neurosecretory protein GL (NPGL), which is involved in energy homeostasis in birds and mammals. However, whether the action of NPGL is influenced by nutritional composition remains unknown. Thus, we investigated the effect of chronic intracerebroventricular infusion of NPGL for 13 days on feeding behavior and body mass gain under a normal chow (NC) diet, high-fat diet, high-sucrose diet (HSD), and medium-fat/medium-sucrose diet (MFSD) in rats. NPGL stimulated food intake of NC and MFSD, especially during the light period. By contrast, NPGL decreased body mass gain under NC and increased total white adipose tissue mass in HSD- and MFSD-fed rats. These data suggest that the effects of NPGL on feeding behavior, body mass gain, and fat accumulation depend on nutrient type. Among them, sucrose in diets seems to contribute to fat accumulation elicited by NPGL.
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Affiliation(s)
- Keisuke Fukumura
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
| | - Kenshiro Shikano
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan.,Department of Neurophysiology, Faculty of Medicine, Oita University, Oita, Japan
| | - Yuki Narimatsu
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
| | - Eiko Iwakoshi-Ukena
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
| | - Megumi Furumitsu
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
| | - Mana Naito
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
| | - Kazuyoshi Ukena
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Hiroshima, Japan
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Narimatsu Y, Fukumura K, Iwakoshi-Ukena E, Mimura A, Furumitsu M, Ukena K. Subcutaneous infusion of neurosecretory protein GL promotes fat accumulation in mice. Heliyon 2021; 7:e07502. [PMID: 34296011 PMCID: PMC8282975 DOI: 10.1016/j.heliyon.2021.e07502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 04/21/2021] [Accepted: 07/03/2021] [Indexed: 11/19/2022] Open
Abstract
We recently identified a novel small secretory protein, neurosecretory protein GL (NPGL), in the vertebrate hypothalamus. We revealed that NPGL is involved in energy homeostasis using intracerebroventricular infusion in rodents. However, the effect of NPGL through peripheral administration remains to be elucidated and may be important for therapeutic use. In this study, we performed subcutaneous infusion of NPGL in mice for 12 days and found that it accelerated fat accumulation in white adipose tissue (WAT) without increasing in body mass gain and food intake. The mass of the testis, liver, kidney, heart, and gastrocnemius muscle remained unchanged. Analysis of mRNA expression by quantitative reverse transcription-polymerase chain reaction showed that proopiomelanocortin was suppressed in the hypothalamus by the infusion of NPGL. We observed a decreasing tendency in serum triglyceride levels due to NPGL, while serum glucose, insulin, leptin, and free fatty acids levels were unchanged. These results suggest that the peripheral administration of NPGL induces fat accumulation in WAT via the hypothalamus.
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Fukumura K, Narimatsu Y, Moriwaki S, Iwakoshi-Ukena E, Furumitsu M, Ukena K. Effects of Overexpression of Neurosecretory Protein GL-Precursor Gene on Glucose Homeostasis and Insulin Sensitivity in Mice. Int J Mol Sci 2021; 22:4681. [PMID: 33925193 PMCID: PMC8125475 DOI: 10.3390/ijms22094681] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 04/24/2021] [Accepted: 04/26/2021] [Indexed: 12/31/2022] Open
Abstract
A high-fat diet (HFD) quickly induces obesity with insulin resistance and hyperglycemia. We previously reported that a novel hypothalamic small protein, named neurosecretory protein GL (NPGL), stimulates feeding and fat accumulation in mice. However, the effects of NPGL on insulin sensitivity and glucose homeostasis remain unknown. Hence, we subjected NPGL-precursor gene (Npgl)-overexpressing mice to the oral glucose tolerance test (OGTT) and intraperitoneal insulin tolerance test (IPITT) under normal chow (NC) and HFD conditions. Npgl overexpression promoted body mass gain and tended to increase food intake of NC-fed mice, whereas it had little effect on HFD-fed mice. The OGTT showed elevated blood glucose and insulin levels in Npgl-overexpressing NC-fed mice 15 min after glucose administration. Both the OGTT and IPITT demonstrated that Npgl overexpression decreased blood glucose levels in HFD-fed mice 60 min after glucose and insulin treatments. Notably, Npgl overexpression increased adipose tissue masses only in NC-fed mice, and it decreased blood glucose and insulin levels in HFD-fed mice at the experimental end point. It also increased the mRNA expression of galanin, one of the feeding and metabolic regulatory neuropeptides, in the hypothalamus of HFD-fed mice. Therefore, NPGL may alleviate HFD-induced hyperglycemia and insulin resistance in mice.
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Affiliation(s)
| | | | | | | | | | - Kazuyoshi Ukena
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan; (K.F.); (Y.N.); (S.M.); (E.I.-U.); (M.F.)
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Kadota A, Iwakoshi-Ukena E, Fukumura K, Shikano K, Narimatsu Y, Furumitsu M, Ukena K. Effects of Irregular Feeding on the Daily Fluctuations in mRNA Expression of the Neurosecretory Protein GL and Neurosecretory Protein GM Genes in the Mouse Hypothalamus. Int J Mol Sci 2021; 22:2109. [PMID: 33672695 PMCID: PMC7924315 DOI: 10.3390/ijms22042109] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 02/15/2021] [Accepted: 02/18/2021] [Indexed: 01/25/2023] Open
Abstract
Circadian desynchrony induced by a long period of irregular feeding leads to metabolic diseases, such as obesity and diabetes mellitus. The recently identified neurosecretory protein GL (NPGL) and neurosecretory protein GM (NPGM) are hypothalamic small proteins that stimulate food intake and fat accumulation in several animals. To clarify the mechanisms that evoke feeding behavior and induce energy metabolism at the appropriate times in accordance with a circadian rhythm, diurnal fluctuations in Npgl and Npgm mRNA expression were investigated in mice. Quantitative RT-PCR analysis revealed that the mRNAs of these two genes were highly expressed in the mediobasal hypothalamus during the active dark phase under ad libitum feeding. In mice restricted to 3 h of feeding during the inactive light phase, the Npgl mRNA level was augmented in the moment prior to the feeding period and the midnight peak of Npgm mRNA was attenuated. Moreover, the mRNA expression levels of clock genes, feeding regulatory neuropeptides, and lipid metabolic enzymes in the central and peripheral tissues were comparable to those of central Npgl and Npgm. These data suggest that Npgl and Npgm transcription fluctuates daily and likely mediates feeding behavior and/or energy metabolism at an appropriate time according to the meal timing.
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Affiliation(s)
- Atsuki Kadota
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan; (A.K.); (E.I.-U.); (K.F.); (K.S.); (Y.N.); (M.F.)
| | - Eiko Iwakoshi-Ukena
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan; (A.K.); (E.I.-U.); (K.F.); (K.S.); (Y.N.); (M.F.)
| | - Keisuke Fukumura
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan; (A.K.); (E.I.-U.); (K.F.); (K.S.); (Y.N.); (M.F.)
| | - Kenshiro Shikano
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan; (A.K.); (E.I.-U.); (K.F.); (K.S.); (Y.N.); (M.F.)
- Department of Neurophysiology, Faculty of Medicine, Oita University, Yufu, Oita 879-5593, Japan
| | - Yuki Narimatsu
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan; (A.K.); (E.I.-U.); (K.F.); (K.S.); (Y.N.); (M.F.)
| | - Megumi Furumitsu
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan; (A.K.); (E.I.-U.); (K.F.); (K.S.); (Y.N.); (M.F.)
| | - Kazuyoshi Ukena
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan; (A.K.); (E.I.-U.); (K.F.); (K.S.); (Y.N.); (M.F.)
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14
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Moriwaki S, Narimatsu Y, Fukumura K, Iwakoshi-Ukena E, Furumitsu M, Ukena K. Effects of Chronic Intracerebroventricular Infusion of RFamide-Related Peptide-3 on Energy Metabolism in Male Mice. Int J Mol Sci 2020; 21:ijms21228606. [PMID: 33203104 PMCID: PMC7698077 DOI: 10.3390/ijms21228606] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 11/10/2020] [Accepted: 11/12/2020] [Indexed: 12/12/2022] Open
Abstract
RFamide-related peptide-3 (RFRP-3), the mammalian ortholog of avian gonadotropin-inhibitory hormone (GnIH), plays a crucial role in reproduction. In the present study, we explored the other functions of RFRP-3 by investigating the effects of chronic intracerebroventricular infusion of RFRP-3 (6 nmol/day) for 13 days on energy homeostasis in lean male C57BL/6J mice. The infusion of RFRP-3 increased cumulative food intake and body mass. In addition, the masses of brown adipose tissue (BAT) and the liver were increased by the administration of RFRP-3, although the mass of white adipose tissue was unchanged. On the other hand, RFRP-3 decreased O2 consumption, CO2 production, energy expenditure, and core body temperature during a short time period in the dark phase. These results suggest that the increase in food intake and the decrease in energy expenditure contributed to the gain of body mass, including the masses of BAT and the liver. The present study shows that RFRP-3 regulates not only reproductive function, but also energy metabolism, in mice.
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Shikano K, Iwakoshi-Ukena E, Saito T, Narimatsu Y, Kadota A, Furumitsu M, Bentley GE, Kriegsfeld LJ, Ukena K. Neurosecretory protein GL induces fat accumulation in mice. J Endocrinol 2020; 244:1-12. [PMID: 31536964 DOI: 10.1530/joe-19-0112] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 09/18/2019] [Indexed: 11/08/2022]
Abstract
We recently discovered a novel gene encoding a small secretory protein, neurosecretory protein GL (NPGL), which stimulates feeding behavior in mice following acute administration. These findings suggest that dysregulation of NPGL contributes to obesity and metabolic disease. To explore this possibility, we investigated the impact of prolonged exposure to NPGL through 13 days of chronic intracerebroventricular (i.c.v.) infusion and examined feeding behavior, body composition, expressions of lipid metabolic factors, respiratory metabolism, locomotor activity, and food preference. Under standard chow diet, NPGL increased white adipose tissue (WAT) mass without affecting feeding behavior and body mass. In contrast, when fed a high-calorie diet, NPGL stimulated feeding behavior and increased body mass concomitant with marked fat accumulation. Quantitative reverse transcription polymerase chain reaction (RT-PCR) analysis revealed that mRNA expressions for key enzymes and related factors involved in lipid metabolism were increased in WAT and liver. Likewise, analyses of respiratory metabolism and locomotor activity revealed that energy expenditure and locomotor activity were significantly decreased by NPGL. In contrast, selective feeding of macronutrients did not alter food preference in response to NPGL, although total calorie intake was increased. Immunohistochemical analysis revealed that NPGL-containing cells produce galanin, a neuropeptide that stimulates food intake. Taken together, these results provide further support for NPGL as a novel regulator of fat deposition through changes in energy intake and locomotor activity.
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Affiliation(s)
- Kenshiro Shikano
- Laboratory of Neuroendocrinology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan
- Department of Neurophysiology, Faculty of Medicine, Oita University, Yufu, Oita, Japan
| | - Eiko Iwakoshi-Ukena
- Laboratory of Neuroendocrinology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan
| | - Takaya Saito
- Laboratory of Neuroendocrinology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan
| | - Yuki Narimatsu
- Laboratory of Neuroendocrinology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan
| | - Atsuki Kadota
- Laboratory of Neuroendocrinology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan
| | - Megumi Furumitsu
- Laboratory of Neuroendocrinology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan
| | - George E Bentley
- Department of Integrative Biology and the Helen Wills Neuroscience Institute, University of California, Berkeley, California, USA
| | - Lance J Kriegsfeld
- Department of Psychology and the Helen Wills Neuroscience Institute, University of California, Berkeley, California, USA
| | - Kazuyoshi Ukena
- Laboratory of Neuroendocrinology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan
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Shikano K, Iwakoshi-Ukena E, Kato M, Furumitsu M, Bentley GE, Kriegsfeld LJ, Ukena K. Neurosecretory Protein GL Induces Fat Accumulation in Chicks. Front Endocrinol (Lausanne) 2019; 10:392. [PMID: 31275247 PMCID: PMC6593053 DOI: 10.3389/fendo.2019.00392] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 05/31/2019] [Indexed: 01/27/2023] Open
Abstract
We recently found a previously unidentified cDNA in chicken hypothalamus which encodes the precursor for neurosecretory protein GL (NPGL). A previous study showed that intracerebroventricular (i.c.v.) infusion of NPGL caused body mass gain in chicks. However, it was not clear which part(s) of the body gained mass. In the present study, we investigated which tissues increased in mass after chronic i.c.v. infusion of NPGL in chicks. We found that NPGL increased the masses of the liver, abdominal fat, and subcutaneous fat, while NPGL did not affect the masses of muscles, including pectoralis major, pectoralis minor, and biceps femoris. Oil Red O staining revealed that fat deposition had occurred in the liver. In addition, the size of the lipid droplets in the abdominal fat increased. Furthermore, we found an upregulation of lipogenesis and downregulation of lipolysis in the abdominal fat, but not in the liver. These results indicate that NPGL is involved in fat storage in chicks.
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Affiliation(s)
- Kenshiro Shikano
- Laboratory of Neuroendocrinology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
- Department of Neurophysiology, Faculty of Medicine, Oita University, Yufu, Japan
| | - Eiko Iwakoshi-Ukena
- Laboratory of Neuroendocrinology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
| | - Masaki Kato
- Laboratory of Neuroendocrinology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
| | - Megumi Furumitsu
- Laboratory of Neuroendocrinology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
| | - George E. Bentley
- Department of Integrative Biology, Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, United States
| | - Lance J. Kriegsfeld
- Department of Psychology, Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, United States
| | - Kazuyoshi Ukena
- Laboratory of Neuroendocrinology, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
- *Correspondence: Kazuyoshi Ukena
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Shikano K, Taniuchi S, Iwakoshi-Ukena E, Furumitsu M, Bentley GE, Kriegsfeld LJ, Ukena K. Chronic subcutaneous infusion of neurosecretory protein GM increases body mass gain in chicks. Gen Comp Endocrinol 2018; 265:71-76. [PMID: 29155267 DOI: 10.1016/j.ygcen.2017.11.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 11/13/2017] [Accepted: 11/15/2017] [Indexed: 11/22/2022]
Abstract
Recently we discovered a small hypothalamic protein in the chicken, named neurosecretory protein GL (NPGL), which is associated with body growth and energy metabolism in birds and rodents. Genome database analysis suggested that the NPGL gene has a paralogous gene in vertebrates, named neurosecretory protein GM (NPGM). However, the biological action of NPGM remains unclear. In this study, we investigated whether NPGM affects body growth in chicks. We found that subcutaneous infusion of NPGM for six days increased body mass gain in a dose-dependent manner. Despite the observed increase in body mass, infusion of NPGM did not alter food and water intake. Of note, we observed tendency of mass increase of several peripheral tissues, specifically. When we compared several tissue types, NPGM seemed to induce the largest growth increase in white adipose tissue mass. These results suggest that NPGM may accelerate fat accumulation and body growth. In addition, we analyzed whether NPGM increases body growth through the action of pituitary hormones. However, we observed no significant changes in mRNA expression of pituitary hormones or plasma levels of growth hormone in NPGM-treated chicks. This is the first report describing the biological action of NPGM in vertebrates.
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Affiliation(s)
- Kenshiro Shikano
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Shusuke Taniuchi
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Eiko Iwakoshi-Ukena
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan; Department of Integrative Biology and The Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, CA 94720-3140, USA
| | - Megumi Furumitsu
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - George E Bentley
- Department of Integrative Biology and The Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, CA 94720-3140, USA
| | - Lance J Kriegsfeld
- Department of Psychology and the Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, CA 94720-3140, USA
| | - Kazuyoshi Ukena
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan; Department of Psychology and the Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, CA 94720-3140, USA.
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18
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Shikano K, Bessho Y, Kato M, Iwakoshi-Ukena E, Taniuchi S, Furumitsu M, Tachibana T, Bentley GE, Kriegsfeld LJ, Ukena K. Localization and function of neurosecretory protein GM, a novel small secretory protein, in the chicken hypothalamus. Sci Rep 2018; 8:704. [PMID: 29335496 PMCID: PMC5768754 DOI: 10.1038/s41598-017-18822-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 12/18/2017] [Indexed: 12/15/2022] Open
Abstract
Recently, we discovered a novel cDNA encoding the precursor of a small secretory protein, neurosecretory protein GL (NPGL), in the hypothalamic infundibulum of chickens. NPGL plays an important role in the regulation of growth and feeding. A database search indicated that the NPGL gene has a paralogous gene: neurosecretory protein GM (NPGM), also in chickens. We identified cDNA encoding the NPGM precursor in chickens. Morphological analysis showed that NPGM-containing cells are specifically localized in the medial mammillary nucleus (MM) and infundibular nucleus (IN) in the hypothalamus. In addition, we found that NPGM and NPGL are co-localized, especially in the MM. The expression levels of NPGM mRNA gradually decreased during post-hatch development, in contrast to those of NPGL mRNA. Moreover, we investigated the relationship between NPGM and other known factors. NPGM was found to be produced in histaminergic neurons in the MM. NPGM and histidine decarboxylase, a histamine-producing enzyme, displayed similar expression patterns during post-hatch development. Acute intracerebroventricular injection of NPGM decreased food intake, similar to the effect of histamine. To our knowledge, this is the first report of the localization and function of NPGM in the brain of vertebrates. These results will further advance the understanding mechanisms underlying energy homeostasis.
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Affiliation(s)
- Kenshiro Shikano
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi, Hiroshima, 739-8521, Japan
| | - Yuki Bessho
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi, Hiroshima, 739-8521, Japan
| | - Masaki Kato
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi, Hiroshima, 739-8521, Japan
| | - Eiko Iwakoshi-Ukena
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi, Hiroshima, 739-8521, Japan.,Department of Integrative Biology and the Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, CA, 94720-3140, USA
| | - Shusuke Taniuchi
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi, Hiroshima, 739-8521, Japan
| | - Megumi Furumitsu
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi, Hiroshima, 739-8521, Japan
| | - Tetsuya Tachibana
- Department of Agrobiological Science, Faculty of Agriculture, Ehime University, Matsuyama, 790-8566, Japan
| | - George E Bentley
- Department of Integrative Biology and the Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, CA, 94720-3140, USA
| | - Lance J Kriegsfeld
- Department of Psychology and the Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, CA, 94720-3140, USA
| | - Kazuyoshi Ukena
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi, Hiroshima, 739-8521, Japan. .,Department of Psychology and the Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, CA, 94720-3140, USA.
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Shikano K, Kato M, Iwakoshi-Ukena E, Furumitsu M, Matsuura D, Masuda K, Tachibana T, Bentley GE, Kriegsfeld LJ, Ukena K. Effects of chronic intracerebroventricular infusion of neurosecretory protein GL on body mass and food and water intake in chicks. Gen Comp Endocrinol 2018; 256:37-42. [PMID: 28554734 DOI: 10.1016/j.ygcen.2017.05.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 05/17/2017] [Accepted: 05/24/2017] [Indexed: 12/17/2022]
Abstract
Recently, we discovered a novel cDNA encoding the precursor of a small secretory protein, neurosecretory protein GL (NPGL), in the chicken mediobasal hypothalamus. In this study, immunohistochemical analysis revealed that NPGL was produced in the infundibular and medial mammillary nuclei of the mediobasal hypothalamus, with immunoreactive fibers also detected in the hypothalamus and the median eminence. As it is known that these regions are involved in feeding behavior in chicks, we surveyed the effects of chronic intracerebroventricular infusion of NPGL on feeding behavior and body mass for a period of two weeks. NPGL stimulated food and water intake, with a concomitant increase in body mass. However, NPGL did not influence mRNA expression of several hypothalamic ingestion-related neuropeptides. Our data suggest that NPGL may be a novel neuronal regulator involved in growth processes in chicks.
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Affiliation(s)
- Kenshiro Shikano
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Masaki Kato
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Eiko Iwakoshi-Ukena
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan; Department of Integrative Biology, The Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, CA 94720-3140, USA
| | - Megumi Furumitsu
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Daichi Matsuura
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Keiko Masuda
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Tetsuya Tachibana
- Department of Agrobiological Science, Faculty of Agriculture, Ehime University, Matsuyama 790-8566, Japan
| | - George E Bentley
- Department of Integrative Biology, The Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, CA 94720-3140, USA
| | - Lance J Kriegsfeld
- Department of Psychology, The Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, CA 94720-3140, USA
| | - Kazuyoshi Ukena
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan; Department of Psychology, The Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, CA 94720-3140, USA.
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Iwakoshi-Ukena E, Shikano K, Kondo K, Taniuchi S, Furumitsu M, Ochi Y, Sasaki T, Okamoto S, Bentley GE, Kriegsfeld LJ, Minokoshi Y, Ukena K. Neurosecretory protein GL stimulates food intake, de novo lipogenesis, and onset of obesity. eLife 2017; 6. [PMID: 28799896 PMCID: PMC5553934 DOI: 10.7554/elife.28527] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 07/10/2017] [Indexed: 02/06/2023] Open
Abstract
Mechanisms underlying the central regulation of food intake and fat accumulation are not fully understood. We found that neurosecretory protein GL (NPGL), a newly-identified neuropeptide, increased food intake and white adipose tissue (WAT) in rats. NPGL-precursor gene overexpression in the hypothalamus caused increases in food intake, WAT, body mass, and circulating insulin when fed a high calorie diet. Intracerebroventricular administration of NPGL induced de novo lipogenesis in WAT, increased insulin, and it selectively induced carbohydrate intake. Neutralizing antibody administration decreased the size of lipid droplets in WAT. Npgl mRNA expression was upregulated by fasting and low insulin levels. Additionally, NPGL-producing cells were responsive to insulin. These results point to NPGL as a novel neuronal regulator that drives food intake and fat deposition through de novo lipogenesis and acts to maintain steady-state fat level in concert with insulin. Dysregulation of NPGL may be a root cause of obesity. DOI:http://dx.doi.org/10.7554/eLife.28527.001 Throughout history, our ancestors needed to accumulate fat to survive during times when food sources were scarce. However, for most people in the modern age, food is abundant and eating too much is a major cause of weight gain, obesity and diseases affecting the metabolism. Obesity in particular, can lead to diseases such as diabetes and heart disease. Hunger and appetite are regulated by proteins and other chemicals that act as messengers, for example insulin, and a region of the brain called the hypothalamus. However, the full mechanisms that regulate these sensations remain unclear. Only recently, a protein called NPGL was discovered in a part of the hypothalamus of birds and mammals. However, it was not known if NPGL plays a role in regulating eating habits and weight gain. Iwakoshi-Ukena et al. have now discovered that NPGL is found in the hypothalamus of rats and is regulated by diet and insulin. When the gene for NPGL was manipulated to produce too much of the protein, rats fed a high calorie diet started to eat more, and gained more weight and body fat. Adding additional NPGL to their brains had the same effect. When the animals were fed a normal diet, NPGL only moderately affected how much they ate, but it substantially increased how much fat they produced. Iwakoshi-Ukena et al. also observed that when animals were starved and insulin levels were low, the rats started to produce more NPGL. These results suggest that NPGL plays a role in fat storage when energy sources are limited, and can contribute to obesity when too much NPGL is produced in animals on a high calorie diet. These findings indicate that NPGL could be an additional brain chemical that regulates hunger and fat storage in mammals. A next step will be to reveal the specific mechanisms by which NPGL regulates overeating and fat accumulation. These findings will further advance the study and treatment of obesity and obesity-related diseases. DOI:http://dx.doi.org/10.7554/eLife.28527.002
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Affiliation(s)
- Eiko Iwakoshi-Ukena
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima, Japan.,Department of Integrative Biology and The Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, United States
| | - Kenshiro Shikano
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima, Japan
| | - Kunihiro Kondo
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima, Japan
| | - Shusuke Taniuchi
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima, Japan
| | - Megumi Furumitsu
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima, Japan
| | - Yuta Ochi
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima, Japan
| | - Tsutomu Sasaki
- Laboratory of Metabolic Signal, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Japan
| | - Shiki Okamoto
- Division of Endocrinology and Metabolism, Department of Homeostatic Regulation, National Institute for Physiological Sciences, Okazaki, Japan.,Department of Physiological Sciences, School of Life Science, Sokendai (The Graduate University for Advanced Studies), Hayama, Japan.,Second Department of Internal Medicine (Endocrinology, Diabetes and Metabolism, Hematology, Rheumatology), Graduate School of Medicine, University of the Ryukyus, Nakagami-gun, Japan
| | - George E Bentley
- Department of Integrative Biology and The Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, United States
| | - Lance J Kriegsfeld
- Department of Psychology and The Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, United States
| | - Yasuhiko Minokoshi
- Division of Endocrinology and Metabolism, Department of Homeostatic Regulation, National Institute for Physiological Sciences, Okazaki, Japan.,Department of Physiological Sciences, School of Life Science, Sokendai (The Graduate University for Advanced Studies), Hayama, Japan
| | - Kazuyoshi Ukena
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima, Japan.,Department of Psychology and The Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, United States
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21
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Matsuura D, Shikano K, Saito T, Iwakoshi-Ukena E, Furumitsu M, Ochi Y, Sato M, Bentley GE, Kriegsfeld LJ, Ukena K. Neurosecretory Protein GL, a Hypothalamic Small Secretory Protein, Participates in Energy Homeostasis in Male Mice. Endocrinology 2017; 158:1120-1129. [PMID: 28323972 PMCID: PMC6283432 DOI: 10.1210/en.2017-00064] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Accepted: 03/13/2017] [Indexed: 11/19/2022]
Abstract
We have recently identified from the avian hypothalamus a complementary DNA encoding a small secretory protein termed neurosecretory protein GL (NPGL). In chicks, NPGL increases body weight gain without affecting food intake. A database search reveals that NPGL is conserved throughout vertebrates. However, the central distribution and functional role of NPGL remains to be elucidated in mammals. In this study, we identified the precursor complementary DNA encoding NPGL from the mouse hypothalamus. Quantitative reverse transcription polymerase chain reaction and morphological analyses revealed that NPGL precursor messenger RNA is robustly expressed in the mediobasal hypothalamus with NPGL neurons specifically localized to the lateroposterior part of the arcuate nucleus in the hypothalamus. NPGL-immunoreactive fibers were observed in close anatomical contact with pro-opiomelanocortin neurons in the rostral region of the arcuate nucleus. NPGL messenger RNA expression was elevated by 24-hour fasting and reduced by feeding of a high-fat diet for 5 weeks. Furthermore, intracerebroventricular injection of mature NPGL increased food intake, pointing to an important role in feeding. Taken together, these findings report on the distribution of NPGL in the mammalian brain and point to an important role for this neuropeptide in energy homeostasis.
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Affiliation(s)
- Daichi Matsuura
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Kenshiro Shikano
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Takaya Saito
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Eiko Iwakoshi-Ukena
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
- Department of Integrative Biology, The Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, California 94720
| | - Megumi Furumitsu
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Yuta Ochi
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Manami Sato
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - George E Bentley
- Department of Integrative Biology, The Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, California 94720
| | - Lance J Kriegsfeld
- Department of Psychology, The Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, California 94720
| | - Kazuyoshi Ukena
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
- Department of Psychology, The Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, California 94720
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22
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Masuda K, Furumitsu M, Ooyama H, Iwakoshi-Ukena E, Ukena K. Synthesis of neurosecretory protein GM composed of 88 amino acid residues by native chemical ligation. Tetrahedron Lett 2016. [DOI: 10.1016/j.tetlet.2016.01.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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23
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Masuda K, Ooyama H, Shikano K, Kondo K, Furumitsu M, Iwakoshi-Ukena E, Ukena K. Microwave-assisted solid-phase peptide synthesis of neurosecretory protein GL composed of 80 amino acid residues. J Pept Sci 2015; 21:454-60. [DOI: 10.1002/psc.2756] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2014] [Revised: 12/10/2014] [Accepted: 01/07/2015] [Indexed: 11/11/2022]
Affiliation(s)
- Keiko Masuda
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences; Hiroshima University; Higashi-Hiroshima 739-8521 Japan
| | - Haruka Ooyama
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences; Hiroshima University; Higashi-Hiroshima 739-8521 Japan
| | - Kenshiro Shikano
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences; Hiroshima University; Higashi-Hiroshima 739-8521 Japan
| | - Kunihiro Kondo
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences; Hiroshima University; Higashi-Hiroshima 739-8521 Japan
| | - Megumi Furumitsu
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences; Hiroshima University; Higashi-Hiroshima 739-8521 Japan
| | - Eiko Iwakoshi-Ukena
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences; Hiroshima University; Higashi-Hiroshima 739-8521 Japan
| | - Kazuyoshi Ukena
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences; Hiroshima University; Higashi-Hiroshima 739-8521 Japan
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24
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Masuda K, Iwakoshi-Ukena E, Bessho Y, Taniuchi S, Maejima S, Shikano K, Kondo K, Furumitsu M, Ukena K. Identification of neurotensin and LANT-6 and localization of mRNA encoding their precursor in the chicken brain. Zoolog Sci 2014; 31:353-9. [PMID: 24882095 DOI: 10.2108/zs140010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Neurotensin (NT) and neurotensin-related peptide (Lys(8), Asn(9), NT(8-13): LANT-6) have previously been purified from chicken intestine. However, the presence of these peptides and the localization of their precursor mRNA in the brain were not well understood. In the present study, through a comprehensive analysis of bioactive substances, NT and LANT-6 were identified in the chicken brain using tandem mass spectrometry combined with a bioassay of the colon contraction. The effect of NT and LANT-6 on the colon contraction was assessed, and NT was found to be 10 times more potent than LANT-6. Furthermore, the sites of NT/LANT-6 precursor mRNA expression in the brain were investigated using quantitative RT-PCR. The result showed that the mRNA was expressed most in the telencephalon, followed by the diencephalon. In situ hybridization analysis revealed that cells containing NT/LANT-6 precursor mRNA were widely distributed throughout the brain except for the cerebellum. Additionally, these were highly concentrated in the frontal telencephalon, including the nidopallium, hyperpallium, and hippocampus. Collectively, these results indicate that NT and LANT-6 are produced in the chicken brain, and they may participate in multiple functions.
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Affiliation(s)
- Keiko Masuda
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
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25
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Bessho Y, Iwakoshi-Ukena E, Tachibana T, Maejima S, Taniuchi S, Masuda K, Shikano K, Kondo K, Furumitsu M, Ukena K. Characterization of an avian histidine decarboxylase and localization of histaminergic neurons in the chicken brain. Neurosci Lett 2014; 578:106-10. [DOI: 10.1016/j.neulet.2014.06.048] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2014] [Revised: 05/17/2014] [Accepted: 06/13/2014] [Indexed: 11/30/2022]
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26
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Ukena K, Iwakoshi-Ukena E, Taniuchi S, Bessho Y, Maejima S, Masuda K, Shikano K, Kondo K, Furumitsu M, Tachibana T. Identification of a cDNA encoding a novel small secretory protein, neurosecretory protein GL, in the chicken hypothalamic infundibulum. Biochem Biophys Res Commun 2014; 446:298-303. [PMID: 24582750 DOI: 10.1016/j.bbrc.2014.02.090] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 02/22/2014] [Indexed: 11/24/2022]
Abstract
To find novel neuropeptide and/or peptide hormone precursors in the avian brain, we performed a cDNA subtractive screen of the chicken hypothalamic infundibulum, which contains one of the feeding and neuroendocrine centers. After sequencing 596 clones, we identified a novel cDNA encoding a previously unknown protein. The deduced precursor protein consisted of 182 amino acid residues, including one putative small secretory protein of 80 amino acid residues. This small protein was flanked at the N-terminus by a signal peptide and at the C-terminus by a glycine amidation signal and a dibasic amino acid cleavage site. Because the predicted C-terminal amino acids of the small protein were Gly-Leu-NH2, the small protein was named neurosecretory protein GL (NPGL). Quantitative RT-PCR analysis demonstrated specific expression of the NPGL precursor mRNA in the hypothalamic infundibulum. Furthermore, the mRNA levels in the hypothalamic infundibulum increased during post-hatching development. In situ hybridization analysis showed that the cells containing the NPGL precursor mRNA were localized in the medial mammillary nucleus and infundibular nucleus within the hypothalamic infundibulum of 8- and 15-day-old chicks. Subcutaneous infusion of NPGL in chicks increased body weight gain without affecting food intake. To our knowledge, this is the first report to describe the identification and localization of the NPGL precursor mRNA and the function of its translated product in animals. Our findings indicate that NPGL may participate in the growth process in chicks.
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Affiliation(s)
- Kazuyoshi Ukena
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan.
| | - Eiko Iwakoshi-Ukena
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Shusuke Taniuchi
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Yuki Bessho
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Sho Maejima
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Keiko Masuda
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Kenshiro Shikano
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Kunihiro Kondo
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Megumi Furumitsu
- Section of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
| | - Tetsuya Tachibana
- Department of Agrobiological Science, Faculty of Agriculture, Ehime University, Matsuyama 790-8566, Japan
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