Mikiya Miyazato

National Cerebral and Cardiovascular Center, Ōsaka, Ōsaka, Japan

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Publications (102)303.69 Total impact

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    ABSTRACT: C-type natriuretic peptide (CNP), secreted by vascular endothelial cells, belongs to a family of peptides that includes atrial and brain natriuretic peptides. CNP exhibits many vasoprotective effects against pulmonary hypertension and pulmonary fibrosis. The objective of this study was to investigate the prophylactic effects of CNP in a mouse model of lipopolysaccharide (LPS)-induced acute lung injury (ALI). C57BL/6 mice were divided into three groups as follows: normal control mice (n = 13), LPS mice treated with vehicle (n = 12), and LPS mice treated with CNP (n = 12). Twenty-four hours after tail vein injection of LPS, histopathologic, gene expression, and bronchoalveolar lavage fluid (BALF) assessments were performed on the lungs. To examine the neutrophils in the lungs, cells positive for myeloperoxidase staining were detected by immunohistochemistry. BALF cytokine levels were analyzed by enzyme-linked immunosorbent assays. Gene expression in lung tissue was analyzed by real-time polymerase chain reaction. CNP significantly attenuated the elevation of leukocyte cell counts and levels of tumor necrosis factor-alpha, macrophage inflammatory protein-2, monocyte chemoattractant protein-1, interleukin-6, and keratinocyte-derived chemokine in the BALF after LPS injection. Furthermore, there were significantly fewer myeloperoxidase-positive cells in lungs treated with CNP after LPS injection. In lungs of CNP-treated mice, expression of the monocyte chemoattractant protein-1, S100A8, and E-selectin genes was significantly lower than that in vehicle-treated mice. CNP had a protective effect on ALI induced by LPS by reducing inflammatory cell infiltration. CNP may hold promise in therapeutic strategies for ALI after pulmonary resection surgery. Copyright © 2014 Elsevier Inc. All rights reserved.
    Journal of Surgical Research 11/2014; · 2.02 Impact Factor
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    ABSTRACT: Cisplatin is an effective chemotherapeutic agent used in the treatment of a wide variety of malignancies. Acute kidney injury (AKI) is the major toxicity associated with cisplatin and sometimes necessitates a reduction in dose or discontinuation of treatment. Atrial natriuretic peptide (ANP) is secreted by the heart and exerts a wide range of renoprotective effects, including anti-inflammatory activity. The objective of this study was to investigate the protective effects of ANP on cisplatin-induced AKI in mice.
    Cancer Chemotherapy and Pharmacology 11/2014; · 2.80 Impact Factor
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    ABSTRACT: Intrauterine growth retardation (IUGR) occurs in 3–7% of all pregnancies. Recent human studies have indicated that neurodevelopmental disabilities, learning disorders, memory impairment, and mood disturbance are common in IUGR offspring. However, the interactions between IUGR and neurodevelopmental disorders are unclear because of the wide range of causes of IUGR, such as maternal malnutrition, placental insufficiency, pregnancy toxemia, and fetal malformations. Meanwhile, many studies have shown that moderate food restriction enhances spatial learning and improves mood disturbance in adult humans and animals. To date, the effects of maternal moderate food restriction on fetal brain remain largely unknown. In this study, we hypothesized that IUGR would be caused by even moderate food restriction in pregnant females, and that the offspring would have neurodevelopmental disabilities. Mid-pregnant mice received moderate food restriction through the early lactation period. The offspring were tested for aspects of physical development, behavior, and neurodevelopment. The results showed that moderate maternal food restriction induced IUGR. Offspring had low birth weight and delayed development of physical and coordinated movement. Moreover, IUGR offspring exhibited mental disabilities such as anxiety and poor cognitive function. In particular, male offspring exhibited significantly impaired cognitive function at 3 weeks of age. These results suggested that a restricted maternal diet could be a risk factor for developmental disability in IUGR offspring, and that male offspring might be especially susceptible.
    Nutrition Research. 11/2014;
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    ABSTRACT: We identified two ghrelin receptor isoforms, the ghrelin receptor type-1a (GHS-R1a) and its alternative splice form (GHS-R1b) for West African lungfish, Protopterus annectens. Lungfish GHS-R1a and 1b comprised 361 and 281 amino acids, respectively. Lungfish GHS-R1a showed the highest identity to coelacanth GHS-R1a (80.4%). The highest expression of GHS-R1a mRNAs was seen in the brain, liver, ovary, heart, intestine, and gills. GHS-R1b mRNAs were also detected in the same tissues with GHS-R1a, but their expression level was 1/20 that of GHS-R1a. In human embryonic kidney 293 cells transiently expressing lungfish GHS-R1a, rat and bullfrog ghrelin, and two GHS-R1a agonists, GHRP-6 and hexarelin, increased intracellular Ca(2+) concentrations. The intensity of the Ca(2+) increases induced by GHS-R1a agonists was twice when compared to that induced by ghrelin, although the median effective doses (ED50) were similar, suggesting a long-lasting effect of GHS-R1a agonists with similar affinity. We also examined changes in the GHS-R gene expression during an eight-week estivation. Body weight was slightly lowered, but plasma sodium and glucose concentrations decreased; plasma urea concentration increased significantly 4 weeks after the start of estivation. Overall, expression of GHS-R1a mRNA decreased, but changes in GHS-R1b mRNA expression were inconsistent with those of GHS-R1a during estivation, suggesting an involvement of GHS-R in energy homeostasis, as seen in mammals. Our results suggest that the ghrelin-GHS-R1a system is present in this lungfish although ghrelin has not yet been found. The structure of GHS-R1a is closer to that of tetrapods than Actinopterygian fish, indicating a process of evolution that follows the Crossopterygii such as coelacanth.
    General and Comparative Endocrinology 08/2014; · 2.82 Impact Factor
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    ABSTRACT: Neuromedin U (NMU) are bioactive peptides with a common C-terminal heptapeptide-sequence (FLFRPRN-amide, 1a) among mammals, which is responsible for receptor activation, namely NMU receptors types 1 (NMUR1) and 2 (NMUR2). Among the various physiological actions of NMU, the anorexigenic effect has recently attracted attention in drug discovery efforts for treating obesity. Although several structure-activity relationship (SAR) studies have been reported, receptor-selective small peptide agonists have yet to be disclosed. Herein an SAR study of 1a-derived peptide derivatives is described. We initially screened both human NMUR1 and NMUR2 selective peptides in calcium-mobilization assays with cells transiently expressing receptors. Then we performed a precise assay with a stable expression system of receptors, and consequently discovered hexapeptides 8d and 6b possessing selective agonist activity towards each respective receptor. Hexapeptide 6b, which selectively activates NMUR2 without significant NMUR1 activation, should aid in the development of anorexigenic drugs as well as advance NMU-related endocrinological research.
    Journal of Medicinal Chemistry 07/2014; · 5.61 Impact Factor
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    ABSTRACT: Both hexarelin and its natural analog ghrelin exert comparable cardioprotective activities. A single dose of ghrelin administered at the very acute phase after experimental myocardial infarction positively affects cardiac function in chronic heart failure. Therefore, this study aimed to determine whether a single dose of oral hexarelin has the same effect in the chronic disease phase. Myocardial infarction or sham operation was generated by left coronary artery ligation in male C57BL/6J mice, which subsequently received one dose of hexarelin or vehicle treatment by oral gavage 30minutes after operation. Although the mortality within 14 days after myocardial infarction did not differ between the groups, hexarelin treatment protected cardiac function in the chronic phase as evidenced by higher ejection fraction and fractional shortening, as well as lower lung weight/body weight and lung weight/tibial length ratios, compared with vehicle treatment. Hexarelin treatment concurrently lowered plasma epinephrine and dopamine levels, and shifted the balance of autonomic nervous activity toward parasympathetic nervous activity as evidenced by a smaller low/high-frequency power ratio and larger normalized high-frequency power on heart rate variability analysis. The results first demonstrate that one dose of oral hexarelin treatment potentially protects chronic cardiac function after acute myocardial infarction, and implicate that activating growth hormone secretagogue receptor 1a might be beneficial for cardioprotection, although other mechanism may also be involved.
    Peptides 04/2014; · 2.52 Impact Factor
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    ABSTRACT: We recently reported that administration of atrial natriuretic peptide during the perioperative period has prophylactic effects with respect to not only cardiovascular but also respiratory complications following pulmonary resection. However, its mechanisms are not well understood. The objective of the present study was to investigate the mechanism of the prophylactic effects of atrial natriuretic peptide in an acute lung injury model. For the evaluation of the early phase of pulmonary inflammation, in vitro and in vivo studies using lipopolysaccharide were used. In the in vitro study, the effects of atrial natriuretic peptide on the induction of E-selectin by lipopolysaccharide in human pulmonary artery endothelial cells were evaluated. In the in vivo study, the effects of atrial natriuretic peptide on lipopolysaccharide-induced inflammatory cell infiltration and cytokine levels including tumor necrosis factor-alpha and interleukin-6 in the bronchoalveolar lavage fluid in the lungs of C57/B6 mice were examined. The number of myeloperoxidase-positive staining cells in the tissue sections of the lung of lipopolysaccharide-administered C57/B6 mice was also evaluated. Atrial natriuretic peptide significantly attenuated the up-regulation of E-selectin expression induced by lipopolysaccharide in human pulmonary artery endothelial cells. There were significantly lower cell counts and levels of tumor necrosis factor-alpha and interleukin-6 in the bronchoalveolar lavage fluid of atrial natriuretic peptide-treated mice compared to control mice after lipopolysaccharide injection. In addition, there were significantly fewer myeloperoxidase-positive cells in atrial natriuretic peptide-treated mice than in control mice after lipopolysaccharide injection. Atrial natriuretic peptide had a protective effect in the lipopolysaccharide-induced acute lung injury model. Atrial natriuretic peptide may be of value in therapeutic strategies aimed at the treatment of acute lung injury such as pneumonia or acute respiratory distress syndrome.
    Pulmonary Pharmacology &amp Therapeutics 01/2014; · 2.54 Impact Factor
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    ABSTRACT: Both hexarelin and its natural analog ghrelin exert comparable cardioprotective activities. A single dose of ghrelin administered at the very acute phase after experimental myocardial infarction positively affects cardiac function in chronic heart failure. Therefore, this study aimed to determine whether a single dose of oral hexarelin has the same effect in the chronic disease phase. Myocardial infarction or sham operation was generated by left coronary artery ligation in male C57BL/6J mice, which subsequently received one dose of hexarelin or vehicle treatment by oral gavage 30 min after operation. Although the mortality within 14 days after myocardial infarction did not differ between the groups, hexarelin treatment protected cardiac function in the chronic phase as evidenced by higher ejection fraction and fractional shortening, as well as lower lung weight/body weight and lung weight/tibial length ratios, compared with vehicle treatment. Hexarelin treatment concurrently lowered plasma epinephrine and dopamine levels, and shifted the balance of autonomic nervous activity toward parasympathetic nervous activity as evidenced by a smaller low/high-frequency power ratio and larger normalized high-frequency power on heart rate variability analysis. The results first demonstrate that one dose of oral hexarelin treatment potentially protects chronic cardiac function after acute myocardial infarction, and implicate that activating growth hormone secretagogue receptor 1a might be beneficial for cardioprotection, although other mechanism may also be involved.
    Peptides 01/2014; · 2.52 Impact Factor
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    ABSTRACT: Ghrelin is a peptide that was originally isolated from the stomach. It exerts potent growth hormone (GH)-releasing and orexigenic activities. Several studies have highlighted the therapeutic benefits of ghrelin for the treatment of cardiovascular disease. In animal models of chronic heart failure, the administration of ghrelin improved cardiac function and remodeling; these findings were replicated in human patients with heart failure. Moreover, in an animal study, ghrelin administration effectively reduced pulmonary hypertension induced by chronic hypoxia. In addition, repeated administration of ghrelin to cachectic patients with chronic obstructive pulmonary disease had positive effects on overall body function, including muscle wasting, functional capacity and sympathetic activity. The administration of ghrelin early after myocardial infarction (MI) reduced fatal arrhythmia and related mortality. In ghrelin-deficient mice, both exogenous and endogenous ghrelin were protective against fatal arrhythmia and promoted remodeling after MI. Although the mechanisms underlying the effects of ghrelin on the cardiovascular system remain unclear, there are indications that its beneficial effects are mediated through both direct physiological actions, including increased GH levels, improved energy balance and direct actions on cardiovascular cells, and regulation of autonomic nervous system activity. Therefore, ghrelin is a promising novel therapeutic agent for cardiovascular disease. © 2014 S. Karger AG, Basel.
    Frontiers of hormone research 01/2014; 43:125-33. · 1.24 Impact Factor
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    ABSTRACT: Background and purpose Most therapeutic agents are administered intravenously (IV) in clinical settings and intraperitoneally (IP) in preclinical studies with neonatal rodents; however, it remains unclear whether intraperitoneal (IP) injection is truly an acceptable alternative for intravenous (IV) injection in preclinical studies. The objective of our study is to clarify the differences in the therapeutic effects of drugs and in the distribution of infused cells after an IP or IV injection in animals with brain injury. Methods Dexamethasone or MK-801, an N-methyl-d-aspartate receptor antagonist was administered either IP or IV in a mouse model of neonatal hypoxic–ischemic encephalopathy. Green fluorescent protein-expressing mesenchymal stem cells (MSCs) or mononuclear cells (MNCs) were injected IP or IV in the mouse model. Two hours and 24 h after the administration of the cells, we investigated the cell distributions by immunohistochemical staining. We also investigated distribution of IV administered MNCs labeled with 2-[18F]fluoro-2-deoxy-d-glucose in a juvenile primate, a macaque with stroke 1 h after the administration. Results IP and IV administration of dexamethasone attenuated the brain injury to a similar degree. IP administration of MK-801 attenuated brain injury, whereas IV administration of MK-801 did not. The IV group showed a significantly greater number of infused cells in the lungs and brains in the MSC cohort and in the spleen, liver, and lung in the MNC cohort compared to the IP group. In the macaque, MNCs were detected in the spleen and liver in large amounts, but not in the brain and lungs. Conclusions This study demonstrated that the administration route influences the effects of drugs and cell distribution. Therefore, a preclinical study may need to be performed using the optimal administration route used in a clinical setting.
    Brain and Development. 01/2014;
  • Hiroyuki Kaiya, Kenji Kangawa, Mikiya Miyazato
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    ABSTRACT: After the discovery in 1996 of the growth hormone secretagogue-receptor type-1a (GHS-R1a) as an orphan G-protein coupled receptor, many research groups attempted to identify the endogenous ligand. Finally, Kojima and colleagues successfully isolated the peptide ligand from rat stomach extracts, determined its structure, and named it ghrelin (Kojima et al. 1999). The GHS-R1a is now accepted to be the ghrelin receptor. The existence of the ghrelin system has been demonstrated in many animal classes through biochemical and molecular biological strategies as well as through genome projects. Our work, which has concentrated on identifying the ghrelin receptor and its ligand ghrelin in laboratory animals, particularly non-mammalian vertebrates, has provided new insights into the molecular evolution of the ghrelin receptor. In mammals, it is assumed that the ghrelin receptor evolution is in line with the plate tectonics theory. In contrast, the evolution of the ghrelin receptor in non-mammalian vertebrates differs from that of mammals: multiplicity of the ghrelin receptor isoforms is observed in non-mammalian vertebrates only. This multiplicity is due to genome duplication and polyploidization events that particularly occurred in Teleostei. Furthermore, it is likely that the evolution of the ghrelin receptor is distinct from that of its ligand, ghrelin, since only one ghrelin isoform has been detected in all species examined so far. In this review, we summarize current knowledge related to the molecular evolution of the ghrelin receptor in mammalian and non-mammalian vertebrates.
    Journal of Molecular Endocrinology 12/2013; · 3.58 Impact Factor
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    ABSTRACT: Mesenchymal stem cell (MSC) transplantation has been pursued as a new method to repair damaged myocardium. We focused on the fetal membrane (FM) as an alternative source to bone marrow (BM)-derived MSCs. In this study, we investigated whether transplantation of allogeneic FM-MSC sheets could attenuate myocardial dysfunction in a rat chronic myocardial infarction (MI) model. Sheets of allogeneic FM-MSC or autologous BM-MSC were transplanted into the scarred myocardium 4 weeks after coronary ligation. Four weeks after transplantation, both allogeneic FM-MSC and autologous BM-MSC sheets had significantly improved cardiac function and reduced myocardial fibrosis compared with the untreated MI group. In both MSC sheet-transplanted groups, the peri-infarct regional capillary density was increased. Some engrafted MSCs formed vascular structures and were positive for lectin I and α-smooth muscle actin. The numbers of engrafted cells and differentiated cells were very low after both types of MSC sheet transplantation. CD3 T cells did not increase in the transplantation site, but CD163 M2 macrophages increased in the groups transplanted with allogeneic FM-MSC and autologous BM-MSC. Transplantation of allogeneic FM-MSC or autologous BM-MSC sheets attenuated myocardial dysfunction in a rat MI model to a similar degree. The engraftment rate of transplanted cells and immune cell infiltration into the transplanted area did not differ between the two types of MSC transplants. M2 macrophage induction has possible involvement in the therapeutic effects of MSC transplantation. Allogeneic FM-MSC sheet transplantation might be a new therapeutic strategy after MI.
    Transplantation 08/2013; · 3.78 Impact Factor
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    ABSTRACT: Both ghrelin and the synthetic analogue hexarelin are reported to possess cardioprotective actions that are mainly exerted through different receptors. However, their effects on acute myocardial infarction have not been compared in vivo. This study aimed to clarify whether hexarelin treatment can compensate for ghrelin deficiency in ghrelin knockout mice, and to compare the effects of hexarelin (400 nmol/kg per day, s.c.) and equimolar ghrelin treatment after myocardial infarction. Myocardial infarction was produced by left coronary artery ligation in male ghrelin-knockout mice, which then received ghrelin, hexarelin, or vehicle treatment for 2 weeks. The mortality within 2 weeks was significantly lower in the hexarelin group (6.7%) and ghrelin group (14.3%) than in the vehicle group (50%) (P < 0.05). A comparison of cardiac function 2 weeks post-infarction showed that in the ghrelin and hexarelin treatment groups, cardiac output were greater, while systolic function, represented by ejection fraction, and diastolic function, represented by dP/dt min, were significantly superior compared to the vehicle group (P < 0.05). Hexarelin treatment was more effective than ghrelin treatment, as indicated by the ejection fraction, dP/dt max, and dP/dt min. Telemetry recording and heart rate variability analysis demonstrated that sympathetic nervous activity was clearly suppressed in the hexarelin and ghrelin groups relative to the vehicle group. Our data demonstrated that hexarelin treatment can result in better heart function than ghrelin treatment 2 weeks after myocardial infarction in ghrelin knockout mice, although both hormones have similar effects on heart rate variability and mortality.
    Endocrinology 07/2013; · 4.72 Impact Factor
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    Hiroyuki Kaiya, Kenji Kangawa, Mikiya Miyazato
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    ABSTRACT: Ghrelin is a peptide found in the mucosal layer of the rat stomach that exhibits growth hormone-releasing and appetite-stimulating activities. Since the discovery of ghrelin in chicken in 2002, information on its structure, distribution, function, and receptors has been accumulated, mainly in poultry. Here, we summarize the following findings since 2008 in birds: (1) central ghrelin acts as an anorexigenic neuropeptide, but the effect of peripheral ghrelin differs depending on the chicken strain and light conditions the birds are kept in; (2) central ghrelin inhibits not only food intake but also water drinking, and it may be mediated by urocortin, a member of the corticotropin-releasing factor family; (3) peripheral ghrelin acts as an anti-lipogenic factor in broiler chickens but not in rats; (4) the enzyme involved in ghrelin acylation (ghrelin-O-acyltransferase [GOAT]) has been identified in chickens; (5) dietary lipids are used for ghrelin acylation; (6) des-acyl ghrelin administered alone or with ghrelin does not affect feeding behavior; (7) the existence and physiological function of obestatin must now be carefully examined in birds; (8) other than the growth hormone secretagogue receptors (GHS) R1a and 1b, GHS-R variants not found in mammals have been found in chicken and Japanese quail; and finally (9) little is known about the involvement of the ghrelin system in wild birds and in avian-specific behavior such as brooding and migration.
    General and Comparative Endocrinology 04/2013; · 2.82 Impact Factor
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    ABSTRACT: Background: We have previously demonstrated the protective role of endogenous ghrelin against malignant arrhythmias in the very acute phase of myocardial infarction (MI). However, the role of endogenous ghrelin in the chronic phase is unknown. Therefore, the aim of the current study was to focus on the effects of endogenous ghrelin on cardiac function and sympathetic activation after acute MI. Methods and results: In 46 ghrelin-knockout (KO) and 41 wild-type (WT) male mice, MI was produced by left coronary artery ligation. The mortality due to heart failure within 2 weeks was 0% in WT and 10.9% in KO (P < 0.05). At the end of this period, lung weight/tibial length, atrial natriuretic peptide and brain natriuretic peptide transcripts, end-systolic and end-diastolic volumes were all significantly greater in KO mice, whereas systolic function, represented by ejection fraction (16.4 ± 4.7% vs. 25.3 ± 5.1%), end-systolic elastance, and preload-recruitable stroke work, was significantly inferior to that in WT mice (P < 0.05). Telemetry recording and heart rate variability analysis showed that KO mice had stronger sympathetic activation after MI than did WT mice. Metoprolol treatment and ghrelin treatment in KO mice prevented excessive sympathetic activation, decreased plasma epinephrine and norepinephrine levels, and improved heart function and survival rate after MI. Conclusions: Our data demonstrate that endogenous ghrelin plays a crucial role in protecting heart function and reducing mortality after myocardial infarction, and that these effects seem to be partly the result of sympathetic inhibition.
    Endocrinology 03/2013; · 4.72 Impact Factor
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    ABSTRACT: Urotensin II (UII) and UII-related peptide (URP) exhibit diverse physiological actions including vasoconstriction, locomotor activity, osmoregulation, and immune response through UII receptor (UTR), which is expressed in the central nervous system and peripheral tissues of fish and mammals. In amphibians, only UII has been identified. As the first step toward elucidating the actions of UII and URP in amphibians, we cloned and characterized URP and UTR from the African clawed frog Xenopus laevis. Functional analysis showed that treatment of UII or URP with Chinese hamster ovary cells transfected with the cloned receptor increased the intracellular calcium concentration in a concentration-dependent manner, whereas the administration of the UTR antagonist urantide inhibited UII- or URP-induced Ca2+ mobilization. An immunohistochemical study showed that UTR was expressed in the splenocytes and leukocytes isolated from peripheral blood, suggesting that UII and URP are involved in the regulation of the immune system. UTR was also localized in the apical membrane of the distal tubule of the kidney and in the transitional epithelial cells of the urinary bladder. This result supports the view that the UII/URP-UTR system plays an important role in osmoregulation of amphibians. Interestingly, immunopositive labeling for UTR was first detected in the chondrocytes of various hyaline cartilages (the lung septa, interphalangeal joint and sternum). The expression of UTR was also observed in the costal cartilage, tracheal cartilages, and xiphoid process of the rat. These novel findings probably suggest that UII and URP mediate the formation of the cartilaginous matrix.
    General and Comparative Endocrinology 02/2013; 185C:44-56. · 2.82 Impact Factor
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    Dataset: YGCEN 11343
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    Hiroyuki Kaiya, Kenji Kangawa, Mikiya Miyazato
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    ABSTRACT: The growth hormone secretagogue-receptor (GHS-R) was discovered in humans and pigs in 1996. The endogenous ligand, ghrelin, was discovered 3 years later, in 1999, and our understanding of the physiological significance of the ghrelin system in vertebrates has grown steadily since then. Although the ghrelin system in non-mammalian vertebrates is a subject of great interest, protein sequence data for the receptor in non-mammalian vertebrates has been limited until recently, and related biological information has not been well organized. In this review, we summarize current information related to the ghrelin receptor in non-mammalian vertebrates.
    Frontiers in Endocrinology 01/2013; 4:81.
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    ABSTRACT: Ghrelin is a peptide hormone that is acylated with a fatty acid, usually n-octanoic acid, at the third amino acid (aa) residue (usually a serine or threonine), and this acylation is known to be essential for ghrelin activity not only in mammals but also in non-mammals, such as fish. However, the modification mechanisms of ghrelin modification in fish are not known. In this study, we elucidated the structure of ghrelin in a teleost, the barfin flounder (Verasper moseri), and determined whether ingested free fatty acids of various chain lengths participated in ghrelin acylation. Complementary DNA cloning revealed the barfin flounder prepro-ghrelin to be a 106-aa peptide and the mature ghrelin to be a 20-aa peptide (GSSFLSPSHKPPNKGKPPRA). However, purification of ghrelin peptides from stomach extracts demonstrated that the major form of the hormone was a 19-aa decanoylated peptide [GSS(C10:0)FLSPSHKPPNKGKPPR] missing the last alanine of the 20-aa peptide. Ingestion of feed enriched with n-heptanoic acid (C7), n-octanoic acid (C8), or n-non-anoic acid (C9) changed the modification status of the peptide: ingestion of C8 or C9 increased the amount of C8:0 or C9:0 19-aa ghrelin, respectively, but no C7:0 ghrelin was isolated after ingestion of C7. These results indicate that ingested free fatty acids are substrates for ghrelin acylation in the barfin flounder, but the types of free fatty acids utilized as substrates may be limited.
    Frontiers in Endocrinology 01/2013; 4:117.
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Publication Stats

2k Citations
303.69 Total Impact Points

Institutions

  • 1997–2014
    • National Cerebral and Cardiovascular Center
      • Department of Cardiovascular Medicine
      Ōsaka, Ōsaka, Japan
  • 2010–2013
    • University of Toyama
      • Department of Radiological Sciences
      Тояма, Toyama, Japan
    • Kurume University
      • Division of Molecular Genetics
      Куруме, Fukuoka, Japan
  • 2008–2011
    • Nippon Veterinary and Life Science University
      Edo, Tōkyō, Japan
  • 2004–2011
    • Miyazaki University
      • Faculty of Agriculture
      Miyazaki-shi, Miyazaki-ken, Japan
  • 2003
    • Oita University
      Ōita, Ōita, Japan