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Liu J, Li J, Zhai N, Geng L, Song F. Detection of the Levels of Neuropeptides, ACTH and Cortisol in the Blood of Patients with Polymyositis/Dermatomyositis and Their Significance. J Dermatol 2014; 31:392-7. [PMID: 15187306 DOI: 10.1111/j.1346-8138.2004.tb00690.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2003] [Accepted: 01/20/2004] [Indexed: 11/30/2022]
Abstract
Recent research has shown that the neuroendocrine system can regulate the function of the immune system and that ACTH and cortisol play important roles in maintaining the immune homeostasis. Polymyositis and dermatomyositis (PM/DM) are autoimmune diseases with unclear pathogeneses closely related with immune disorders, so we detected the levels of neuropeptide Y (NPY), beta-endorphin (beta-EP), calcitonin gene-related peptide (CGRP), adrenocoricotropic hormone (ACTH), and cortisol in blood of patients with PM/DM to investigate the relationship between these indices and the pathogenesis of PM/DM. The detection of NPY, beta-EP, CGRP, and ACTH concentrations in plasma and cortisol in serum of 28 cases of PM/DM was carried out using radioimmunoassay methods, and the results were compared with those of 20 normal controls. The levels of NPY in the plasma of PM/DM was significantly higher than those of the controls, while beta-EP, CGRP and ACTH were significantly lower than those of the controls, and cortisol was not significantly different before treatment. Linear correlation analysis indicated that NPY was significantly positively correlated with CPK, and beta-EP and CGRP were significantly negatively correlated with CPK. There were no significant correlations among cortisol ACTH, and CPK and no significant correlations between NPY, beta-EP, CGRP, ACTH, cortisol and age or duration of disease before treatment. After treatment for three months, NPY, beta-EP and CGRP tended to become normal and no longer significantly different from the control values. However, ACTH fell further and was significantly lower than the level before treatment. Therefore the increase in NPY and the decreases in beta-EP, CGRP, and ACTH in the plasma of PM/DM patients may be related to the pathogenesis of PM/DM.
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Affiliation(s)
- Jifeng Liu
- Department of Dermatology, the First Affliated Hospital of China Medical University, Shenyang 110001 Liaoning Province, China
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2
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Santos-Carvalho A, Álvaro AR, Martins J, Ambrósio AF, Cavadas C. Emerging novel roles of neuropeptide Y in the retina: from neuromodulation to neuroprotection. Prog Neurobiol 2013; 112:70-9. [PMID: 24184719 DOI: 10.1016/j.pneurobio.2013.10.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Revised: 10/14/2013] [Accepted: 10/15/2013] [Indexed: 12/11/2022]
Abstract
Neuropeptide Y (NPY) and NPY receptors are widely expressed in the central nervous system, including the retina. Retinal cells, in particular neurons, astrocytes, and Müller, microglial and endothelial cells express this peptide and its receptors (Y1, Y2, Y4 and/or Y5). Several studies have shown that NPY is expressed in the retina of various mammalian and non-mammalian species. However, studies analyzing the distribution of NPY receptors in the retina are still scarce. Although the physiological roles of NPY in the retina have not been completely elucidated, its early expression strongly suggests that NPY may be involved in the development of retinal circuitry. NPY inhibits the increase in [Ca(2+)]i triggered by elevated KCl in retinal neurons, protects retinal neural cells against toxic insults and induces the proliferation of retinal progenitor cells. In this review, we will focus on the roles of NPY in the retina, specifically proliferation, neuromodulation and neuroprotection. Alterations in the NPY system in the retina might contribute to the pathogenesis of retinal degenerative diseases, such as diabetic retinopathy and glaucoma, and NPY and its receptors might be viewed as potentially novel therapeutic targets.
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Affiliation(s)
- Ana Santos-Carvalho
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Largo Marquês de Pombal, 3004-517 Coimbra, Portugal; Faculty of Pharmacy, University of Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal
| | - Ana Rita Álvaro
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Largo Marquês de Pombal, 3004-517 Coimbra, Portugal; Department of Biology and Environment, University of Trás-os-Montes and Alto Douro, Apartado 1013, 5001-801 Vila Real, Portugal
| | - João Martins
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Largo Marquês de Pombal, 3004-517 Coimbra, Portugal; Centre of Ophthalmology and Vision Sciences, IBILI, Faculty of Medicine, University of Coimbra, Azinhaga de Santa Comba, Celas, 3000-548 Coimbra, Portugal
| | - António Francisco Ambrósio
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Largo Marquês de Pombal, 3004-517 Coimbra, Portugal; Centre of Ophthalmology and Vision Sciences, IBILI, Faculty of Medicine, University of Coimbra, Azinhaga de Santa Comba, Celas, 3000-548 Coimbra, Portugal; AIBILI-Association for Innovation and Biomedical Research on Light and Image, Azinhaga Santa Comba, Celas, 3000-548 Coimbra, Portugal
| | - Cláudia Cavadas
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Largo Marquês de Pombal, 3004-517 Coimbra, Portugal; Faculty of Pharmacy, University of Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal.
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DeMorrow S, Meng F, Venter J, Leyva-Illades D, Francis H, Frampton G, Pae HY, Quinn M, Onori P, Glaser S, McDaniel K, Mancinelli R, Gaudio E, Alpini G, Franchitto A. Neuropeptide Y inhibits biliary hyperplasia of cholestatic rats by paracrine and autocrine mechanisms. Am J Physiol Gastrointest Liver Physiol 2013; 305:G250-7. [PMID: 23703654 PMCID: PMC3742859 DOI: 10.1152/ajpgi.00140.2013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Neuropeptide Y (NPY) exerts its functions through six subtypes of receptors (Y₁-Y₆). Biliary homeostasis is regulated by several factors through autocrine/paracrine signaling. NPY inhibits cholangiocarcinoma growth; however, no information exists regarding the autocrine/paracrine role of NPY on biliary hyperplasia during cholestasis. The aims of this study were to determine: 1) the expression of NPY and Y₁-Y₅ in cholangiocytes and 2) the paracrine/autocrine effects of NPY on cholangiocyte proliferation. Normal or bile duct ligation (BDL) rats were treated with NPY, neutralizing anti-NPY antibody, or vehicle for 7 days. NPY and NPY receptor (NPYR) expression was assessed in liver sections and isolated cholangiocytes. NPY secretion was assessed in serum and bile from normal and BDL rats, as well as supernatants from normal and BDL cholangiocytes and normal rat cholangiocyte cell line [intrahepatic normal cholangiocyte culture (NRICC)]. We evaluated intrahepatic bile ductal mass (IBDM) in liver sections and proliferation in cholangiocytes. With the use of NRICC, the effects of NPY or anti-NPY antibody on cholangiocyte proliferation were determined. The expression of NPY and all NPYR were increased after BDL. NPY levels were lower in serum and cholangiocyte supernatant from BDL compared with normal rats. NPY secretion from NRICC was detected at both the basolateral and apical domains. Chronic NPY treatment decreased proliferating cellular nuclear antigen (PCNA) expression and IBDM in BDL rats. Administration of anti-NPY antibody to BDL rats increased cholangiocyte proliferation and IBDM. NPY treatment of NRICC decreased PCNA expression and increased the cell cycle arrest, whereas treatment with anti-NPY antibody increased proliferation. Therapies targeting NPY-mediated signaling may prove beneficial for the treatment of cholangiopathies.
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Affiliation(s)
- Sharon DeMorrow
- 1Research, Central Texas Veterans Health Care System, Temple, Texas; ,2Scott & White Digestive Disease Research Center, Scott & White, Temple, Texas; ,4Department of Medicine, Division Gastroenterology, Texas A&M Health Science Center, College of Medicine, Temple, Texas;
| | - Fanyin Meng
- 1Research, Central Texas Veterans Health Care System, Temple, Texas; ,2Scott & White Digestive Disease Research Center, Scott & White, Temple, Texas; ,3Division of Research and Education, Scott & White, Temple, Texas; ,4Department of Medicine, Division Gastroenterology, Texas A&M Health Science Center, College of Medicine, Temple, Texas;
| | - Julie Venter
- 4Department of Medicine, Division Gastroenterology, Texas A&M Health Science Center, College of Medicine, Temple, Texas;
| | - Dinorah Leyva-Illades
- 4Department of Medicine, Division Gastroenterology, Texas A&M Health Science Center, College of Medicine, Temple, Texas;
| | - Heather Francis
- 1Research, Central Texas Veterans Health Care System, Temple, Texas; ,2Scott & White Digestive Disease Research Center, Scott & White, Temple, Texas; ,3Division of Research and Education, Scott & White, Temple, Texas; ,4Department of Medicine, Division Gastroenterology, Texas A&M Health Science Center, College of Medicine, Temple, Texas;
| | - Gabriel Frampton
- 4Department of Medicine, Division Gastroenterology, Texas A&M Health Science Center, College of Medicine, Temple, Texas;
| | - Hae Yong Pae
- 4Department of Medicine, Division Gastroenterology, Texas A&M Health Science Center, College of Medicine, Temple, Texas;
| | - Matthew Quinn
- 4Department of Medicine, Division Gastroenterology, Texas A&M Health Science Center, College of Medicine, Temple, Texas;
| | - Paolo Onori
- 5Department of Anatomical, Histological, Forensic Medicine and Orthopedics Sciences, “La Sapienza,” Rome, Italy; and
| | - Shannon Glaser
- 1Research, Central Texas Veterans Health Care System, Temple, Texas; ,2Scott & White Digestive Disease Research Center, Scott & White, Temple, Texas; ,3Division of Research and Education, Scott & White, Temple, Texas; ,4Department of Medicine, Division Gastroenterology, Texas A&M Health Science Center, College of Medicine, Temple, Texas;
| | - Kelly McDaniel
- 3Division of Research and Education, Scott & White, Temple, Texas;
| | - Romina Mancinelli
- 5Department of Anatomical, Histological, Forensic Medicine and Orthopedics Sciences, “La Sapienza,” Rome, Italy; and
| | - Eugenio Gaudio
- 5Department of Anatomical, Histological, Forensic Medicine and Orthopedics Sciences, “La Sapienza,” Rome, Italy; and
| | - Gianfranco Alpini
- 1Research, Central Texas Veterans Health Care System, Temple, Texas; ,2Scott & White Digestive Disease Research Center, Scott & White, Temple, Texas; ,4Department of Medicine, Division Gastroenterology, Texas A&M Health Science Center, College of Medicine, Temple, Texas;
| | - Antonio Franchitto
- 5Department of Anatomical, Histological, Forensic Medicine and Orthopedics Sciences, “La Sapienza,” Rome, Italy; and ,6Eleonora Lorillard Spencer-Cenci Foundation, Rome, Italy
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Gelfo F, De Bartolo P, Tirassa P, Croce N, Caltagirone C, Petrosini L, Angelucci F. Intraperitoneal injection of neuropeptide Y (NPY) alters neurotrophin rat hypothalamic levels: Implications for NPY potential role in stress-related disorders. Peptides 2011; 32:1320-3. [PMID: 21473895 DOI: 10.1016/j.peptides.2011.03.023] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2011] [Revised: 03/29/2011] [Accepted: 03/29/2011] [Indexed: 10/18/2022]
Abstract
Neuropeptide Y (NPY) is a 36-amino acid peptide which exerts several regulatory actions within peripheral and central nervous systems. Among NPY actions preclinical and clinical data have suggested that the anxiolytic and antidepressant actions of NPY may be related to its antagonist action on the hypothalamic-pituitary-adrenal (HPA) axis. The neurotrophins brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) are proteins involved in the growth, survival and function of neurons. In addition to this, a possible role of neurotrophins, particularly BDNF, in HPA axis hyperactivation has been proposed. To characterize the effect of NPY on the production of neurotrophins in the hypothalamus we exposed young adult rats to NPY intraperitoneal administration for three consecutive days and then evaluated BDNF and NGF synthesis in this brain region. We found that NPY treatment decreased BDNF and increased NGF production in the hypothalamus. Given the role of neurotrophins in the hypothalamus, these findings, although preliminary, provide evidence for a role of NPY as inhibitor of HPA axis and support the idea that NPY might be involved in pathologies characterized by HPA axis dysfunctions.
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Affiliation(s)
- Francesca Gelfo
- IRCCS Santa Lucia Foundation, Department of Clinical and Behavioral Neurology, 00179 Rome, Italy.
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5
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Porzionato A, Macchi V, Parenti A, De Caro R. Trophic factors in the carotid body. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2008; 269:1-58. [PMID: 18779056 DOI: 10.1016/s1937-6448(08)01001-0] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The aim of the present study is to provide a review of the expression and action of trophic factors in the carotid body. In glomic type I cells, the following factors have been identified: brain-derived neurotrophic factor, glial cell line-derived neurotrophic factor, artemin, ciliary neurotrophic factor, insulin-like growth factors-I and -II, basic fibroblast growth factor, epidermal growth factor, transforming growth factor-alpha and -beta1, interleukin-1beta and -6, tumour necrosis factor-alpha, vascular endothelial growth factor, and endothelin-1 (ET-1). Growth factor receptors in the above cells include p75LNGFR, TrkA, TrkB, RET, GDNF family receptors alpha1-3, gp130, IL-6Ralpha, EGFR, FGFR1, IL1-RI, TNF-RI, VEGFR-1 and -2, ETA and ETB receptors, and PDGFR-alpha. Differential local expression of growth factors and corresponding receptors plays a role in pre- and postnatal development of the carotid body. Their local actions contribute toward producing the morphologic and molecular changes associated with chronic hypoxia and/or hypertension, such as cellular hyperplasia, extracellular matrix expansion, changes in channel densities, and neurotransmitter patterns. Neurotrophic factor production is also considered to play a key role in the therapeutic effects of intracerebral carotid body grafts in Parkinson's disease. Future research should also focus on trophic actions on carotid body type I cells by peptide neuromodulators, which are known to be present in the carotid body and to show trophic effects on other cell populations, that is, angiotensin II, adrenomedullin, bombesin, calcitonin, calcitonin gene-related peptide, cholecystokinin, erythropoietin, galanin, opioids, pituitary adenylate cyclase-activating polypeptide, atrial natriuretic peptide, somatostatin, tachykinins, neuropeptide Y, neurotensin, and vasoactive intestinal peptide.
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Affiliation(s)
- Andrea Porzionato
- Department of Human Anatomy and Physiology, University of Padova, Padova 35127, Italy
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Conconi MT, Spinazzi R, Nussdorfer GG. Endogenous Ligands of PACAP/VIP Receptors in the Autocrine–Paracrine Regulation of the Adrenal Gland. INTERNATIONAL REVIEW OF CYTOLOGY 2006; 249:1-51. [PMID: 16697281 DOI: 10.1016/s0074-7696(06)49001-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase-activating polypeptide (PACAP) are the main endogenous ligands of a class of G protein-coupled receptors (Rs). Three subtypes of PACAP/VIP Rs have been identified and named PAC(1)-Rs, VPAC(1)-Rs, and VPAC(2)-Rs. The PAC(1)-R almost exclusively binds PACAP, while the other two subtypes bind with about equal efficiency VIP and PACAP. VIP, PACAP, and their receptors are widely distributed in the body tissues, including the adrenal gland. VIP and PACAP are synthesized in adrenomedullary chromaffin cells, and are released in the adrenal cortex and medulla by VIPergic and PACAPergic nerve fibers. PAC(1)-Rs are almost exclusively present in the adrenal medulla, while VPAC(1)-Rs and VPAC(2)-Rs are expressed in both the adrenal cortex and medulla. Evidence indicates that VIP and PACAP, acting via VPAC(1)-Rs and VPAC(2)-Rs coupled to adenylate cyclase (AC)- and phospholipase C (PLC)-dependent cascades, stimulate aldosterone secretion from zona glomerulosa (ZG) cells. There is also proof that they can also enhance aldosterone secretion indirectly, by eliciting the release from medullary chromaffin cells of catecholamines and adrenocorticotropic hormone (ACTH), which in turn may act on the cortical cells in a paracrine manner. The involvement of VIP and PACAP in the regulation of glucocorticoid secretion from inner adrenocortical cells is doubtful and surely of minor relevance. VIP and PACAP stimulate the synthesis and release of adrenomedullary catecholamines, and all three subtypes of PACAP/VIP Rs mediate this effect, PAC(1)-Rs being coupled to AC, VPAC(1)-Rs to both AC and PLC, and VPAC(2)-Rs only to PLC. A privotal role in the catecholamine secretagogue action of VIP and PACAP is played by Ca(2+). VIP and PACAP may also modulate the growth of the adrenal cortex and medulla. The concentrations attained by VIP and PACAP in the blood rule out the possibility that they act as true circulating hormones. Conversely, their adrenal content is consistent with a local autocrine-paracrine mechanism of action.
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Affiliation(s)
- Maria Teresa Conconi
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Padua, I-35121 Padua, Italy
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Nussdorfer GG, Spinazzi R, Mazzocchi G. Cholecystokinin and Adrenal‐Cortex Secretion. VITAMINS AND HORMONES 2005; 71:433-53. [PMID: 16112277 DOI: 10.1016/s0083-6729(05)71015-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
Cholecystokinin, or CCK, is a 33-amino acid peptide, originally considered a gut hormone, that acts via two subtypes of receptors, named CCK1-R and CCK2-R. CCK, along with its receptors, has been subsequently localized in the central nervous system, where it exerts, among other fuctions, antiorexinogenic actions. In this survey, we describe findings indicating that CCK, similar to other peptides modulating food intake (e.g., neuropeptide Y, leptin, and orexins), is also able to regulate the function of the hypothalamo-pituitary-adrenal axis, acting on both its central and peripheral branches. CCK stimulates aldosterone secretion via specific receptors (CCK1-Rs and CCK2-Rs in rats, and CCK2-Rs in humans) located in zona glomerulosa cells and coupled to the adenylate cyclase-dependent signaling cascade; and enhances glucocorticoid secretion from zona fasciculata-reticularis cells via an indirect mechanism mainly involving the CCK2-R-mediated stimulation of corticotropin-releasing hormone-dependent ACTH release.
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Affiliation(s)
- Gastone G Nussdorfer
- Department of Human Anatomy and Physiology, Section of Anatomy, University of Padua, I-35121 Padua, Italy
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8
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Capaldo A, Sciarrillo R, Valiante S, Gay F, Virgilio F, Varlese MG, Laforgia V, Varano L. Neuropeptide Y modulates pituitary-adrenal axis activity in the lizard, Podarcis sicula. Gen Comp Endocrinol 2004; 137:237-47. [PMID: 15201062 DOI: 10.1016/j.ygcen.2004.03.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2003] [Revised: 03/16/2004] [Accepted: 03/22/2004] [Indexed: 11/18/2022]
Abstract
The role of neuropeptide Y (NPY) in the modulation of the pituitary-adrenal axis activity in a lizard, Podarcis sicula, was investigated by in vivo NPY administration. The effects were evaluated by examination of the morphological and morphometrical features of the tissues as well as the plasma levels of ACTH, corticosterone, aldosterone, norepinephrine, and epinephrine. Intraperitoneally administered NPY (27 nmol /100g body wt) raised ACTH plasma levels (from 5.23+/-0.06 pg/ml in carrier injected specimens to 6.83+/-0.01 pg/ml, 24 h after the injection). In the steroidogenic cells a strong decrease of lipid amount was found; corticosterone plasma level increased from 6.28+/-0.02 ng/ml in carrier injected lizards to 7.96+/-0.01 ng/ml 24 h after the injection); aldosterone levels were raised from 1.88+/-0.02 ng/ml in carrier injected specimens to 6.38+/-0.05 ng/ml 24 h after the experimental treatment. In the chromaffin tissue, an increase in the number of epinephrine cells and a decrease in the number of norepinephrine cells were observed, decreasing the numeric norepinephrine/epinephrine (NE/E) cell ratio, from 1.4/1 of control specimens to 0.5/1 24 h after NPY administration. Moreover, norepinephrine plasma level were elevated from 922+/-4.30 pg/ml in carrier injected specimens to 3075+/-11.30 pg/ml 24 h after NPY administration; epinephrine plasma level increased from 502+/-2.40 pg/ml in carrier injected specimens to 2759+/-8.70 pg/ml 24 h after the experimental treatment. Consistent with these findings, morphological observations showed many chromaffin cells weakly stained and with a reduced content of secretory granules. These results suggest that, in P. sicula, NPY may play a role in the modulation of the pituitary-adrenal axis activity. Previous studies localized NPY in the epinephrine cells of P. sicula adrenal gland; taken together, these results suggest that this peptide might participate in the regulation of adrenal gland activity, enhancing corticosteroid and catecholamine secretion in a paracrine/autocrine manner. The mechanism of action of NPY is discussed.
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Affiliation(s)
- Anna Capaldo
- Department of Evolutive and Comparative Biology, University Federico II, 80134 Naples, Italy.
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9
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Abstract
This paper sets out to review several aspects of NPY and adrenal function, starting with the localisation of NPY in the adrenal, then describing the regulation of NPY release and considering whether the adrenal is a significant source of circulating NPY. The review then describes the regulation of adrenal content of peptide, and finally covers the actions of NPY on the adrenal gland, and the receptor subtypes thought to mediate these effects. The regulation and actions of NPY are discussed with reference to both the adrenal cortex and the medulla.
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Affiliation(s)
- D Renshaw
- Department of Endocrinology, Division of General and Developmental Medicine, St Bartholomew's and the Royal London School of Medicine and Dentistry, Queen Mary, University of London, London, UK
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10
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Abstract
The mechanism by which cortisol is produced in adrenal Cushing's syndrome, when ACTH is suppressed, was previously unknown and was referred to as being "autonomous." More recently, several investigators have shown that some cortisol and other steroid-producing adrenal tumors or hyperplasias are under the control of ectopic (or aberrant, illicit, inappropriate) membrane hormone receptors. These include ectopic receptors for gastric inhibitory polypeptide (GIP), beta-adrenergic agonists, or LH/hCG; a similar outcome can result from altered activity of eutopic receptors, such as those for vasopressin (V1-AVPR), serotonin (5-HT4), or possibly leptin. The presence of aberrant receptors places adrenal cells under stimulation by a trophic factor not negatively regulated by glucocorticoids, leading to increased steroidogenesis and possibly to the proliferative phenotype. The molecular mechanisms responsible for the abnormal expression and function of membrane hormone receptors are still largely unknown. Identification of the presence of these illicit receptors can eventually lead to new pharmacological therapies as alternatives to adrenalectomy, now demonstrated by the long-term control of ectopic P-AR- and LH/hCGR-dependent Cushing's syndrome by propanolol and leuprolide acetate. Further studies will potentially identify a larger diversity of hormone receptors capable of coupling to G proteins, adenylyl cyclase, and steroidogenesis in functional adrenal tumors and probably in other endocrine and nonendocrine tumors.
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Affiliation(s)
- A Lacroix
- Department of Medicine, Research Center, H tel du Centre Hospitalier de l'Université de Montréal, Quebec, Canada.
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Abstract
Although several studies have demonstrated the presence of neuropeptide Y (NPY) in nerves supplying the mammalian adrenal cortex, its function in this tissue remains unclear, with reports of both stimulatory and inhibitory effects on aldosterone secretion apparently depending on the tissue preparation used. In the present study the effects of NPY on rat adrenal capsular tissue were investigated. NPY significantly stimulated aldosterone secretion in a dose-dependent manner, and this effect was abolished by atenolol, a beta1-adrenergic antagonist. NPY also stimulated the release of catecholamines from intact rat adrenal capsular tissue with the same dose-dependent relationship as the stimulation of aldosterone release. These observations suggest that the actions of NPY may be mediated by the local release of catecholamines from chromaffin cells within adrenal capsular tissue, as we have previously described for vasoactive intestinal peptide. The second part of this study concerned the NPY receptor subtype mediating the actions of NPY on the adrenal cortex. It was found that peptide YY stimulated aldosterone release with a comparable potency to NPY, whereas pancreatic polypeptide (PP) was without effect. The Y1 selective NPY analog Leu31Pro34NPY had a greater effect on aldosterone release than the Y2 selective analog NPY18-36. Studies using the specific Y1 receptor antagonist BIBP 3226 showed significant attenuation of the aldosterone response to NPY, but no effect on the response to added norepinephrine. Binding studies carried out using [125I]NPY revealed the presence of a single population of NPY-binding sites with a Kd of 12.25 nmol/liter and a binding capacity of 623 fmol/mg protein. Competition studies revealed displacement of [125I]NPY specific binding by NPY, peptide YY, and Leu31Pro34NPY, but not by other peptides. Messenger RNA analysis revealed the presence of messenger RNA coding for both the Y1 receptor and the Y4 receptor, but not the other subtypes. Taken together these data suggest that the effects of NPY on the rat adrenal cortex are mediated by the Y1 receptor subtype.
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Affiliation(s)
- D Renshaw
- Division of Biomedical Sciences, St. Bartholomew's and the Royal London School of Medicine and Dentistry, Queen Mary and Westfield College, United Kingdom
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12
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Abstract
The formation of adrenocortical zonation occurs in rats during late gestation. Since adult cortical function is modulated by neural mediators, it is possible that the development of differentiated function is dependent on cortical innervation. The goal of this study was to compare the pattern and timing of rodent and ovine adrenal innervation during late organogenesis by staining with antibodies directed against the neuropeptides vasoactive intestinal peptide (VIP), calcitonin gene-related peptide (CGRP) and neuropeptide tyrosine (NPY) and the catecholamine biosynthetic enzyme, tyrosine hydroxylase (TOH). Rat adrenals were collected from fetal days 17-21 (term=21 days) and ovine adrenals from fetal days 101-136 (term=145 days). Adrenals were fixed, cryosectioned at 100 microns and immunostained using Cy3-conjugated secondary antibodies. In both species, staining of VIP, CGRP, NPY and TOH fibers was observed in the capsule and subcapsular layers of the cortex during gestation. In late gestation, VIP- and NPY-positive ganglions cells were observed near the medulla extending processes toward the outer cortex; in ovine adrenals, fibers from ganglion cells appeared to surround nests of outer cortical (presumably, zona glomerulosa) cells. These data show that phenotypically distinct neural elements appear at different stages of adrenocortical development. The presence of neural elements in contact with adrenal cortical cells supports the possibility for neural control of adrenocortical development.
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Affiliation(s)
- W C Engeland
- Dept. of Surgery, Graduate Program in Neurosicence, Univ. of Minnesota, Minneapolis 55455, USA.
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Nussdorfer GG, Mazzocchi G. Immune-endocrine interactions in the mammalian adrenal gland: facts and hypotheses. INTERNATIONAL REVIEW OF CYTOLOGY 1998; 183:143-84. [PMID: 9666567 DOI: 10.1016/s0074-7696(08)60144-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Several cytokines, which are the major mediators of the inflammatory responses, are well-known to stimulate the hypothalamopituitary corticotropin-releasing hormone (CRH)/adrenocorticotropic hormone (ACTH) system, thereby evoking secretory responses by the adrenal cortex. Many of these cytokines, including interleukin-1 (IL-1), IL-2, IL-6, tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (INF-gamma) are synthesized in the adrenal gland by both parenchymal cells and resident macrophages, and the release of some of them (e.g., IL-6 and TNF-alpha) is regulated by the main agonists of steroid hormone secretion (e.g., ACTH and angiotensin-II) and bacterial endotoxins. Adrenocortical and adrenomedullary cells are provided with specific receptors for IL-1, IL-2, and IL-6. IL-1 and TNF-alpha directly inhibit aldosterone secretion of zona glomerulosa cells, whereas IL-6 enhances it. IL-2, IL-3, IL-6, and INF-alpha are able to directly stimulate glucocorticoid production by zona fasciculata and zona reticularis cells, whereas IL-1 exerts an analogous effect through an indirect mechanism involving the stimulation of catecholamine release by chromaffin cells and/or the activation of the intramedullary CRH/ACTH system; again, TNF-alpha depresses glucocorticoid synthesis. IL-6 raises androgen secretion by inner adrenocortical layers. IL-1 enhances the proliferation of adrenocortical cells, and findings suggest that cytokines may control the apoptotic deletion of senescent zona reticularis cells. The relevance of the intraadrenal cytokine system in the fine-tuning of the secretion and growth of the adrenal cortex under normal conditions remains to be explored. However, indirect proof is available that local immune-endocrine interactions may play an important role in modulating adrenal responses to inflammatory and immune challenges and stresses.
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Ehrhart-Bornstein M, Hinson JP, Bornstein SR, Scherbaum WA, Vinson GP. Intraadrenal interactions in the regulation of adrenocortical steroidogenesis. Endocr Rev 1998; 19:101-43. [PMID: 9570034 DOI: 10.1210/edrv.19.2.0326] [Citation(s) in RCA: 312] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Mazzocchi G, Gottardo G, Macchi V, Malendowicz LK, Nussdorfer GG. The AT2 receptor-mediated stimulation of adrenal catecholamine release may potentiate the AT1 receptor-mediated aldosterone secretagogue action of angiotensin-II in rats. Endocr Res 1998; 24:17-28. [PMID: 9553752 DOI: 10.3109/07435809809031866] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The role played by AT1 and AT2 receptors in the mediation of angiotensin-II (ANG-II) aldosterone secretagogue action has been investigated in vitro using different types of rat adrenal preparations. ANG-II enhanced aldosterone secretion of dispersed zona glomerulosa (ZG) cells in a concentration-dependent manner (EC50, 3 x 10(-10) M), and its effect was annulled by the AT1-receptor antagonist DuP753 and unaffected by the AT2-receptor antagonist PD123319. ANG-II was significantly more effective in stimulating aldosterone secretion when capsule-ZG and adrenal slices containing medullary chromaffin cells were used (EC50, 1 x 10(-11) M and 7 x 10(-12) M, respectively); moreover, both DuP753 and PD123319 caused partial reversals (intense and moderate, respectively) of the responses to ANG-II, and when added together annulled them. The beta-adrenoceptor antagonist l-alprenolol did not affect aldosterone response to ANG-II of dispersed ZG cells, but exerted a PD123319-like effect on the responses of capsule-ZG and adrenal slices. In light of these findings we conclude that, when the integrity of adrenal tissue is preserved, ANG-II stimulates aldosterone secretion by activating both AT1 and AT2 receptors, the major role being played by AT1 receptors located on ZG cells. The activation of AT2 receptors probably elicits the local release of catecholamines, which in turn enhance aldosterone secretion in a paracrine manner acting through the beta-adrenoceptors with which ZG cells are provided.
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Affiliation(s)
- G Mazzocchi
- Department of Anatomy, University of Padua, Italy
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Abstract
Tachykinins are a family of neuropeptides, which act by binding to three main subtypes of G protein-coupled receptors, named NK1, NK2 and NK3. Tachykinins are contained in both nerve fibers and secretory cells of the hypothalamo-pituitary-adrenal (HPA) axis, and evidence indicates that they take part in the functional control of it. Tachykinins involved in this function include substance P (SP), neuropeptide K and its derivative neurokinin A (NKA), and neurokinin B, which preferentially bind to NK1, NK2 and NK3 receptors, respectively. NK1 agonists exert an inhibitory effect on the hypothalamo pituitary CRH/ACTH system, while NK2 and perhaps NK3 agonists stimulate it, thereby controlling the secretion and growth of the adrenal cortex via circulating ACTH. Intra-adrenal tachykinins may also affect the cortex function. Their direct action on adrenocortical cells is doubtful and probably pharmacologic in nature, but several investigations suggest that tachykinins indirectly stimulate the cortex by acting on medullary chromaffin cells, which in turn exert a paracrine control on adrenocortical cells. SP enhances aldosterone production of zona glomerulosa by eliciting catecholamine secretion; neuropeptide K and NKA raise glucocorticoid production of zonae fasciculata and reticularis through the activation of the intramedullary CRH/ACTH system. The relevance of these effects of tachykinins under basal conditions is questionable, although there are indications that SP is involved in the maintenance of a normal growth and steroidogenic capacity of rat zona glomerulosa, and that SP and NKA play an important role in the stimulation of the adrenal growth during the fetal life. In contrast, evidence has been provided that the role of tachykinins, and especially of SP, could become very relevant under paraphysiological (e.g., physical or inflammatory stresses) or pathological conditions (e.g., ACTH-secreting pituitary tumors), when an excess of steroid-hormone production has to be counteracted.
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Nussdorfer GG, Malendowicz LK. Role of VIP, PACAP, and related peptides in the regulation of the hypothalamo-pituitary-adrenal axis. Peptides 1998; 19:1443-67. [PMID: 9809661 DOI: 10.1016/s0196-9781(98)00102-8] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Vasoactive intestinal polypeptide (VIP) and pituitary adenylate cyclase-activating polypeptide (PACAP) are members of a family of regulatory peptides that are widely distributed in the body and share numerous biologic actions. The two peptides display a remarkable amino acid-sequence homology, and bind to a class of G protein-coupled receptors, named PACAP/VIP receptors (PVRs), whose signaling mechanism mainly involves the activation of adenylate-cyclase and phospholipase-C cascades. A large body of evidence suggests that VIP and PACAP play a role in the control of the hypothalamo--pituitary-adrenal (HPA) axis, almost exclusively acting in a paracrine manner, since their blood concentration is very low. VIP and PACAP are contained in both nerve fibers and neurons of the hypothalamus, and VIP, but not PACAP, is also synthesized in the pituitary gland. Both peptides are expressed in the adrenal gland, and especially in medullary chromaffin cells. All the components of the HPA axis are provided with PVRs. VIP and PACAP enhance pituitary ACTH secretion, VIP by eliciting the hypothalamic release of CRH and potentiating its secretagogue action, and PACAP by directly stimulating pituitary corticotropes. Through this central mechanism, VIP and PACAP may increase mineralo- and glucocorticoid secretion of the adrenal cortex. VIP but not PACAP also exerts a weak direct secretagogue action on adrenocortical cells by activating both PVRs and probably a subtype of ACTH receptors. VIP and PACAP raise aldosterone production via a paracrine indirect mechanism involving the stimulation of medullary chromaffin cells to release catecholamines, which in turn enhance the secretion of zona glomerulosa cells via a beta-adrenoceptor-mediated mechanism. PACAP appears to be able to evoke a glucocorticoid response through the activation, at least in the rat, of the intramedullary CRH/ACTH system. The relevance of these effects of VIP and PACAP under basal conditions is questionable, although there are indications that endogenous VIP is involved in the maintenance of the normal growth and steroidogenic capacity of rat adrenal cortex. However, indirect evidence suggests that these peptides might play a relevant role under paraphysiological conditions (e.g., in the mediation of HPA axis responses to cold and inflammatory stresses) or may be somehow involved in the pathogenesis of Cushing disease or some case of hyperaldosteronism associated with secreting pheochromocytomas.
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Nussdorfer GG, Rossi GP, Belloni AS. The role of endothelins in the paracrine control of the secretion and growth of the adrenal cortex. INTERNATIONAL REVIEW OF CYTOLOGY 1997; 171:267-308. [PMID: 9066130 DOI: 10.1016/s0074-7696(08)62590-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Endothelins (ETs) are a family of vasoactive peptides (ET-1, ET-2, and ET-3) mainly secreted by vascular endothelium and widely distributed in the various body systems, where they play major autocrine/paracrine regulatory functions, acting via two subtypes of receptors (ETA and ETB): Adrenal cortex synthesizes and releases ETS and expresses both ETA and ETB. Zona glomerulosa possesses both ETA and ETB, whereas zona fasciculata/reticularis is almost exclusively provided with ETB. ETS exert a strong mineralocorticoid and a less intense glucocorticoid secretagogue action, mainly via ETB receptors. ETS also appear to enhance the growth and steroidogenic capacity of zona glomerulosa and to stimulate its proliferative activity. This trophic action of ETS is likely to be mediated mainly by ETA receptors. The intraadrenal release of ETS undergoes a multiple regulation, with the rise in blood flow rate and the local release of nitric oxide being the main stimulatory factors. Data are also available that indicate that ETS may also have a role in the pathophysiology of primary aldosteronism caused by adrenal adenomas and carcinomas.
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Nussdorfer GG, Rossi GP, Mazzocchi G. Role of adrenomedullin and related peptides in the regulation of the hypothalamo-pituitary-adrenal axis. Peptides 1997; 18:1079-89. [PMID: 9357070 DOI: 10.1016/s0196-9781(97)00046-6] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Adrenomedullin (ADM) is a hypotensive peptide, originally isolated from human pheochromocytomas, and then found to be widely distributed in the various body systems. ADM derives from preproadrenomedullin, a 185-amino acid residue prohormone, containing at its N-terminal a 20-amino acid sequence, named proadrenomedullin N-terminal 20 peptide (PAMP). ADM and PAMP immunoreactivities have been detected in the hypothalamo-pituitary-adrenal (HPA) axis of humans, rats, and pigs. Adrenal glands possess binding sites for both ADM and PAMP, the former being mainly of the subtype 1 of calcitonin gene-related peptide (CGRP) receptors. ADM exerts a direct inhibitory action on angiotensin II- or potassium-stimulated aldosterone secretion of zona glomerulosa cells. This effect is mediated by the CGRP1 receptor and its mechanism probably involves the blockade of Ca2+ influx. In contrast, ADM enhances aldosterone production by in situ perfused rat adrenals and human adrenal slices (containing medullary chromaffin cells), again through the activation of CGRP1 receptors. This aldosterone secretagogue effect of ADM is blocked by the beta-adrenoceptor antagonist l-alprenolol, thereby suggesting that it is indirectly mediated by the release of catecholamines by chromaffin cells. The effects of ADM on adrenal glucocorticoid release are doubtful and probably mediated by the increase in adrenal blood flow rate and the inhibition of ACTH release by pituitary corticotropes. The concentrations reached by ADM and PAMP in the blood rule out the possibility that they act on the HPA axis as circulating hormones. Conversely, their content in both adrenal and hypothalamo-pituitary complex is consistent with a paracrine mechanism of action, which may play a potentially important role in the regulation of fluid and electrolyte homeostasis.
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Affiliation(s)
- G G Nussdorfer
- Department of Anatomy, University of Padua, Italy. ggnanatipdunidx.unipd.it
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