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Elibol E, Akdevelioğlu Y, Yılmaz C, Narlı B, Şen S, Take Kaplanoğlu G, Seymen CM. Acyl ghrelin, desacyl ghrelin and their ratio affect hepatic steatosis via PPARγ signaling pathway. Arab J Gastroenterol 2024; 25:109-117. [PMID: 38383264 DOI: 10.1016/j.ajg.2023.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 09/11/2023] [Accepted: 12/30/2023] [Indexed: 02/23/2024]
Abstract
BACKGROUND AND STUDY AIMS Ghrelin is an appetite hormone-containing 28-amino acid and has 4 different forms in the body. Ghrelin forms have different physiological functions in the body. This study aims to analyze the effect of acyl and desacyl ghrelin hormone on hepatic steatosis and biochemical findings in 36 male Wistar rats. MATERIALS AND METHODS Rats were split into 6 equal groups, consisting of control, acyl ghrelin, desacyl ghrelin, acyl/desacyl 3:1, acyl/desacyl 1:1, and acyl/desacyl 1:3 groups, and administered placebo or 200 ng/kg hormone subcutaneous twice a day for 14 days. Oral Glucose Tolerance Test (OGTT) was performed on Day 15, Insulin Tolerance Test (ITT) on Day 16, and scarification procedure on Day 17. Certain biochemical data and liver diacylglycerol (DAG), glycogen, protein kinase C and PPAR-γ levels were detected in the blood. Histological analyses were also conducted on the liver tissues. RESULTS The highest plasma total cholesterol and VLDL-K levels were found in the acyl/desacyl 1:3 group, and lower insulin, and HOMA-IR levels were found in groups where acyl and desacyl were administered together (p < 0.05). PPAR-γ gene expression level increased in acyl ghrelin and acyl/desacyl 1:3 groups compared to the control group. Protein kinase C gene expression was highest in the acyl/desacyl 1:3 group. The most severe degenerative findings compliant with steatosis in the liver were observed in the acyl ghrelin group (p < 0.05). CONCLUSION It was determined that administering rats acyl alone and acyl/desacyl by 1:3 caused the highest PPAR-γ gene expression, serum total cholesterol, HDL-K, and VLDL-K levels in the body. Besides, it is shown that desacyl ghrelin effectively regulates the blood glucose level when administered alone.
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Affiliation(s)
- Emine Elibol
- Departments of Nutrition and Dietetic, Ankara Yıldırım Beyazıt University, Dumlupınar Mahallesi, 06760 Çubuk, Ankara, Turkey.
| | - Yasemin Akdevelioğlu
- Departments of Nutrition and Dietetic, Gazi University, Emek mah. Bişkek Cad. 6. Cad. No:2 06490 Çankaya, Ankara, Turkey.
| | - Canan Yılmaz
- Departments of Medical Biochemistry, Gazi University, Faculty of Medicine, 06500 Beşevler, Ankara, Turkey.
| | - Belkıs Narlı
- Departments of Medical Biochemistry, Gazi University, Faculty of Medicine, 06500 Beşevler, Ankara, Turkey.
| | - Serkan Şen
- Departments of Medical Biochemistry, Afyonkarahisar Health Sciences University, Ali Çetinkaya Kampüsü Afyon- İzmir Karayolu 5.km, Afyonkarahisar, Turkey.
| | - Gülnur Take Kaplanoğlu
- Departments of Histology and Embryology, Gazi University Faculty of Medicine, 06500 Beşevler, Ankara, Turkey.
| | - Cemile Merve Seymen
- Departments of Histology and Embryology, Gazi University Faculty of Medicine, 06500 Beşevler, Ankara, Turkey.
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Gajewska A, Strzelecki D, Gawlik-Kotelnicka O. Ghrelin as a Biomarker of "Immunometabolic Depression" and Its Connection with Dysbiosis. Nutrients 2023; 15:3960. [PMID: 37764744 PMCID: PMC10537261 DOI: 10.3390/nu15183960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Revised: 09/08/2023] [Accepted: 09/10/2023] [Indexed: 09/29/2023] Open
Abstract
Ghrelin, a gastrointestinal peptide, is an endogenous ligand of growth hormone secretagogue receptor 1a (GHSR1a), which is mainly produced by X/A-like cells in the intestinal mucosa. Beyond its initial description as a growth hormone (GH) secretagogue stimulator of appetite, ghrelin has been revealed to have a wide range of physiological effects, for example, the modulation of inflammation; the improvement of cardiac performance; the modulation of stress, anxiety, taste sensation, and reward-seeking behavior; and the regulation of glucose metabolism and thermogenesis. Ghrelin secretion is altered in depressive disorders and metabolic syndrome, which frequently co-occur, but it is still unknown how these modifications relate to the physiopathology of these disorders. This review highlights the increasing amount of research establishing the close relationship between ghrelin, nutrition, microbiota, and disorders such as depression and metabolic syndrome, and it evaluates the ghrelinergic system as a potential target for the development of effective pharmacotherapies.
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Affiliation(s)
- Agata Gajewska
- Faculty of Medicine, Medical University of Lodz, 92-216 Lodz, Poland;
| | - Dominik Strzelecki
- Department of Affective and Psychotic Disorders, Medical University of Lodz, 92-216 Lodz, Poland;
| | - Oliwia Gawlik-Kotelnicka
- Department of Affective and Psychotic Disorders, Medical University of Lodz, 92-216 Lodz, Poland;
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Iwakura H, Ensho T, Ueda Y. Desacyl-ghrelin, not just an inactive form of ghrelin?-A review of current knowledge on the biological actions of desacyl-ghrelin. Peptides 2023:171050. [PMID: 37392995 DOI: 10.1016/j.peptides.2023.171050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 06/23/2023] [Accepted: 06/26/2023] [Indexed: 07/03/2023]
Abstract
Desacyl-ghrelin is a form of ghrelin which lacks acyl-modification of the third serine residue of ghrelin. Originally, desacyl-ghrelin was considered to be just an inactive form of ghrelin. More recently, however, it has been suggested to have various biological activities, including control of food intake, growth hormone, glucose metabolism, and gastric movement, and is involved in cell survival. In this review, we summarize the current knowledge of the biological actions of desacyl-ghrelin and the proposed mechanisms by which it exerts the effects.
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Affiliation(s)
- Hiroshi Iwakura
- Department of Pharmacotherapeutics, School of Pharmaceutical Science, Wakayama Medical University, 25-1 Shichibancho, Wakayama 640-8156, Japan.
| | - Takuya Ensho
- Department of Pharmacotherapeutics, School of Pharmaceutical Science, Wakayama Medical University, 25-1 Shichibancho, Wakayama 640-8156, Japan
| | - Yoko Ueda
- Department of Pharmacotherapeutics, School of Pharmaceutical Science, Wakayama Medical University, 25-1 Shichibancho, Wakayama 640-8156, Japan
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Miller JL, Lacroix A, Bird LM, Shoemaker AH, Haqq A, Deal CL, Clark KA, Ames MH, Suico JG, de la Peña A, Fortier C. The Efficacy, Safety, and Pharmacology of a Ghrelin O-Acyltransferase Inhibitor for the Treatment of Prader-Willi Syndrome. J Clin Endocrinol Metab 2022; 107:e2373-e2380. [PMID: 35213714 DOI: 10.1210/clinem/dgac105] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Indexed: 11/19/2022]
Abstract
CONTEXT Acylated ghrelin (AG) stimulates appetite and is elevated compared to its unacylated (UAG) counterpart in Prader-Willi syndrome (PWS). GLWL-01 is a selective, reversible inhibitor of ghrelin O-acyltransferase (GOAT), the enzyme that converts UAG into AG. OBJECTIVE This work aimed to assess the efficacy, pharmacokinetics, pharmacodynamics, and safety of GLWL-01 in the treatment of PWS patients. METHODS A double-blind, placebo-controlled, phase 2 crossover study was conducted with 2 active treatment periods of 28 days in 19 patients (aged 16-65 years; body mass index (BMI) ≥ 28) with genetically confirmed PWS. The study took place in 7 hospital-based study centers in the United States and Canada. Patients received placebo or GLWL-01 (450 mg twice daily) orally after lead-in placebo and washout periods. The Hyperphagia Questionnaire for Clinical Trials and Caregiver Global Impression of Change were used to measure reductions in hyperphagia. Plasma concentrations of AG and UAG were evaluated as correlates. RESULTS Treatment resulted in statistically significant differences compared to placebo in plasma AG (P = .0002), UAG (P = .0488), and AG/UAG (P = .0003). GLWL-01 did not statistically significantly reduce hyperphagia-related behavior or bring about changes in global clinical end points, as assessed by caregivers. Anthropometric and clinical parameters correlated with obesity did not statistically significantly change in response to treatment. Less than half of patients reported a treatment-emergent adverse event (TEAE). No deaths, serious adverse events, or severe TEAEs were reported. CONCLUSION GLWL-01 is safe and well tolerated. Pharmacological parameters confirmed the inhibition of GOAT following administration of GLWL-01. Patients' eating behaviors, BMI, blood glucose, and total cholesterol, among other similar measures, were not modified.
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Affiliation(s)
| | - André Lacroix
- Centre Hospitalier de l'Université de Montréal (CHUM), Montréal, Québec H2X 3J4, Canada
| | - Lynne M Bird
- University of California San Diego and Rady Children's Hospital, San Diego, California 92123, USA
| | | | - Andrea Haqq
- Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta T6G 2T9, Canada
| | - Cheri L Deal
- Centre Hospitalier Universitaire Ste-Justine, Montréal, Québec H3T 1C5, Canada
| | | | - Michael H Ames
- EMB Statistical Solutions LLC, Overland Park, Kansas 66210, USA
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Qian Y, Xia F, Zuo Y, Zhong M, Yang L, Jiang Y, Zou C. Do patients with Prader-Willi syndrome have favorable glucose metabolism? Orphanet J Rare Dis 2022; 17:187. [PMID: 35525976 PMCID: PMC9077846 DOI: 10.1186/s13023-022-02344-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Accepted: 04/26/2022] [Indexed: 11/26/2022] Open
Abstract
Background In recent years, more studies have observed that patients with Prader–Willi syndrome have lower insulin levels and lower insulin resistance than body mass index-matched controls, which may suggest protected glucose metabolism. Method The PubMed and Web of Science online databases were searched to identify relevant studies published in the English language using the terms “Prader–Willi syndrome” with “glucose”, “insulin”, “diabetes mellitus”, “fat”, “adipo*”, “ghrelin”, “oxytocin”, “irisin” or “autonomic nervous system”. Results The prevalence of impaired glucose intolerance, type 2 diabetes mellitus and some other obesity-associated complications in patients with Prader–Willi syndrome tends to be lower when compared to that in general obesity, which is consistent with the hypothetically protected glucose metabolism. Factors including adipose tissue, adiponectin, ghrelin, oxytocin, irisin, growth hormone and the autonomic nervous system possibly modulate insulin sensitivity in patients with Prader–Willi syndrome. Conclusion Although lower insulin levels, lower IR and protected glucose metabolism are widely reported in PWS patients, the causes are still mysterious. Based on existing knowledge, we cannot determine which factor is of utmost importance and what are the underlying mechanisms, and further research is in urgent need.
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Affiliation(s)
- Yanjie Qian
- Department of Endocrinology, The Children's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, No 3333 Binsheng Road, Hangzhou, 310051, China
| | - Fangling Xia
- Department of Endocrinology, The Children's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, No 3333 Binsheng Road, Hangzhou, 310051, China
| | - Yiming Zuo
- Department of Endocrinology, The Children's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, No 3333 Binsheng Road, Hangzhou, 310051, China
| | - Mianling Zhong
- Department of Endocrinology, The Children's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, No 3333 Binsheng Road, Hangzhou, 310051, China
| | - Lili Yang
- Department of Endocrinology, The Children's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, No 3333 Binsheng Road, Hangzhou, 310051, China
| | - Yonghui Jiang
- Department of Genetics, Yale University School of Medicine, New Haven, USA
| | - Chaochun Zou
- Department of Endocrinology, The Children's Hospital of Zhejiang University School of Medicine, National Clinical Research Center for Child Health, No 3333 Binsheng Road, Hangzhou, 310051, China.
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Zang P, Yang CH, Liu J, Lei HY, Wang W, Guo QY, Lu B, Shao JQ. Relationship Between Acyl and Desacyl Ghrelin Levels with Insulin Resistance and Body Fat Mass in Type 2 Diabetes Mellitus. Diabetes Metab Syndr Obes 2022; 15:2763-2770. [PMID: 36105430 PMCID: PMC9464628 DOI: 10.2147/dmso.s368770] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 08/22/2022] [Indexed: 11/23/2022] Open
Abstract
PURPOSE Although strong evidence suggests that ghrelin plays an important role in regulating energy balance, the effects of acylated ghrelin (AG) and deacylated ghrelin (DAG) on fat mass are largely undefined. This study aimed to investigate the differential associations of both forms of ghrelin with insulin resistance and body fat mass in patients with type 2 diabetes mellitus (T2DM). PATIENTS AND METHODS A total of 162 patients with type 2 diabetes were recruited and classified based on BMI and visceral fat area (VFA) as VFA normal group (n = 78), normal-BMI VFA obesity group (n = 20) and high-BMI VFA obesity group (n = 64). VFA and subcutaneous fat area (SFA) were detected by bioelectrical impedance analysis. Blood samples were collected to measure fasting glucose, insulin, lipids, AG and DAG levels after clinical examination. RESULTS Compared with VFA normal group, DAG levels were significantly lower (421.7 ± 106.0 and 388.7 ± 96.5 pg/mL vs 524.4 ± 141.5 pg/mL, P < 0.01) in the two VFA obesity groups. No significant difference was found in AG levels within three groups. Among all subjects, BMI, VFA, SFA, fasting insulin and HOMA-IR were negatively correlated with DAG but positively with AG/DAG ratio (P < 0.01). In contrast, AG was positively correlated with HOMA-IR and fasting glucose (P < 0.01). Multiple stepwise regression analysis showed that fasting glucose was the independent factor of AG, VFA and HOMA-IR were the independent factors related to DAG. CONCLUSION DAG levels have a strong negative association with excess body fat mass and insulin resistance, whereas AG levels are closely related to elevated blood glucose levels in T2DM patients.
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Affiliation(s)
- Pu Zang
- Department of Endocrinology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, People’s Republic of China
| | - Cui-Hua Yang
- Department of Endocrinology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, People’s Republic of China
| | - Jun Liu
- Department of Endocrinology, Jinling Hospital, Southern Medical University, Nanjing, People’s Republic of China
| | - Hai-Yan Lei
- Department of Endocrinology, Jinling Hospital, Southern Medical University, Nanjing, People’s Republic of China
| | - Wei Wang
- Department of Endocrinology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, People’s Republic of China
| | - Qing-Yu Guo
- Department of Endocrinology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, People’s Republic of China
| | - Bin Lu
- Department of Endocrinology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, People’s Republic of China
| | - Jia-Qing Shao
- Department of Endocrinology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, People’s Republic of China
- Correspondence: Jia-Qing Shao, Department of Endocrinology, Jinling Hospital, School of Medicine, Nanjing University, 305 East Zhongshan Road, Nanjing, People’s Republic of China, Tel +86-25-80860354, Email
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Nunez‐Salces M, Li H, Feinle‐Bisset C, Young RL, Page AJ. The regulation of gastric ghrelin secretion. Acta Physiol (Oxf) 2021; 231:e13588. [PMID: 33249751 DOI: 10.1111/apha.13588] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 11/19/2020] [Accepted: 11/23/2020] [Indexed: 12/13/2022]
Abstract
Ghrelin is a gastric hormone with multiple physiological functions, including the stimulation of food intake and adiposity. It is well established that circulating ghrelin levels are closely associated with feeding patterns, rising strongly before a meal and lowering upon food intake. However, the mechanisms underlying the modulation of ghrelin secretion are not fully understood. The purpose of this review is to discuss current knowledge on the circadian oscillation of circulating ghrelin levels, the neural mechanisms stimulating fasting ghrelin levels and peripheral mechanisms modulating postprandial ghrelin levels. Furthermore, the therapeutic potential of targeting the ghrelin pathway is discussed in the context of the treatment of various metabolic disorders, including obesity, type 2 diabetes, diabetic gastroparesis and Prader-Willi syndrome. Moreover, eating disorders including anorexia nervosa, bulimia nervosa and binge-eating disorder are also discussed.
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Affiliation(s)
- Maria Nunez‐Salces
- Vagal Afferent Research Group Adelaide Medical School The University of Adelaide Adelaide SA Australia
- Centre of Research Excellence in Translating Nutritional Science to Good Health Adelaide Medical School The University of Adelaide Adelaide SA Australia
- Nutrition, Diabetes & Gut Health, Lifelong Health Theme South Australian Health & Medical Research Institute (SAHMRI) Adelaide SA Australia
| | - Hui Li
- Vagal Afferent Research Group Adelaide Medical School The University of Adelaide Adelaide SA Australia
- Centre of Research Excellence in Translating Nutritional Science to Good Health Adelaide Medical School The University of Adelaide Adelaide SA Australia
- Nutrition, Diabetes & Gut Health, Lifelong Health Theme South Australian Health & Medical Research Institute (SAHMRI) Adelaide SA Australia
| | - Christine Feinle‐Bisset
- Centre of Research Excellence in Translating Nutritional Science to Good Health Adelaide Medical School The University of Adelaide Adelaide SA Australia
| | - Richard L. Young
- Centre of Research Excellence in Translating Nutritional Science to Good Health Adelaide Medical School The University of Adelaide Adelaide SA Australia
- Nutrition, Diabetes & Gut Health, Lifelong Health Theme South Australian Health & Medical Research Institute (SAHMRI) Adelaide SA Australia
- Intestinal Nutrient Sensing Group Adelaide Medical School The University of Adelaide Adelaide SA Australia
| | - Amanda J. Page
- Vagal Afferent Research Group Adelaide Medical School The University of Adelaide Adelaide SA Australia
- Centre of Research Excellence in Translating Nutritional Science to Good Health Adelaide Medical School The University of Adelaide Adelaide SA Australia
- Nutrition, Diabetes & Gut Health, Lifelong Health Theme South Australian Health & Medical Research Institute (SAHMRI) Adelaide SA Australia
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Fooladi S, Akbari H, Abolhassani M, Sadeghi E, Fallah H. Can Estradiol and Ghrelin Play a Protective Role in Epithelial Ovarian Cancer Incidence in Postmenopausal Women? Arch Med Res 2020; 52:324-331. [PMID: 33250215 DOI: 10.1016/j.arcmed.2020.11.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 10/29/2020] [Accepted: 11/12/2020] [Indexed: 01/04/2023]
Abstract
OBJECTIVE The present study aimed to investigate the association between estradiol, n-octanoylated, des-octanoylated, total ghrelin, and ghrelin/des-octanoylated ghrelin ratio levels along with pathological parameters and epithelial ovarian cancer (EOC) odds in postmenopausal women. MATERIALS AND METHODS A case-control study was carried out on 45 patients with EOC and 33 age-matched postmenopausal women as the control group. Plasma levels of estradiol, n-octanoylated, des-octanoylated, and total ghrelin were measured by ELISA method. RESULTS Estradiol's plasma levels were significantly higher in patients with EOC than in control women (p <0.001). Although the ratio levels of n-octanoylated, des-octanoylated, total ghrelin, and ghrelin/des-octanoylated ghrelin were not associated with EOC in logistic regression models, estradiol levels were significantly related to the increase in EOC odds (OR: 1.083, 95% CI: 1.037-1.13, p <0.001). However, estradiol levels in the two first quartiles (Q1, Q2) were associated with decreased odds of EOC (OR: 0.011, 95% CI: 0.001-0.118, p <0.001, and OR: 0.030, 95% CI: 0.003-0.284, p = 0.002, respectively). For those patients in the third quartile of plasma des-octanoylated and total ghrelin compared to those in the highest (Q4), the multivariate odds ratios of EOC were respectively 0.192 and 0.25. CONCLUSION In conclusion, higher concentrations of des-octanoylated and total ghrelin might be associated with the decreased EOC odds. Furthermore, the findings suggest that high levels of estradiol might be a potential odds factor in EOC, however, lower estradiol levels may have a protective effect on EOC development.
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Affiliation(s)
- Saba Fooladi
- Student Research Committee, School of Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | - Hamed Akbari
- Endocrinology and Metabolism Research Center, Institute of Basic and Clinical Physiology Sciences, Kerman University of Medical Sciences, Kerman, Iran; Department of Clinical Biochemistry, School of Medicine, Kerman University of Medical Sciences, Kerman, Iran.
| | - Moslem Abolhassani
- Student Research Committee, School of Medicine, Kerman University of Medical Sciences, Kerman, Iran; Department of Clinical Biochemistry, School of Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | - Erfan Sadeghi
- Noncommunicable Diseases Research Center, Fasa University of Medical Sciences, Fasa, Iran; Department of Biostatistics and Epidemiology, Faculty of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Hossein Fallah
- Department of Clinical Biochemistry, School of Medicine, Kerman University of Medical Sciences, Kerman, Iran
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Alsaif M, Pakseresht M, Mackenzie ML, Gaylinn B, Thorner MO, Freemark M, Field CJ, Prado CM, Haqq AM. Dietary macronutrient regulation of acyl and desacyl ghrelin concentrations in children with Prader-Willi syndrome (PWS). Clin Endocrinol (Oxf) 2020; 93:579-589. [PMID: 32638409 DOI: 10.1111/cen.14279] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 06/12/2020] [Accepted: 06/30/2020] [Indexed: 11/29/2022]
Abstract
BACKGROUND The effects of dietary macronutrients on orexigenic and anorexigenic hormones in children are poorly understood. OBJECTIVE To explore effects of varying dietary macronutrients on appetite-regulating hormones [acyl ghrelin (AG) and desacyl ghrelin (DAG), glucagon-like peptide 1 (GLP-1), peptide tyrosine tyrosine (PYY) and insulin] in children with PWS and healthy children (HC). DESIGN Randomized, cross-over experiments compared two test diets [high protein-low carbohydrate (HP-LC) and high protein-low fat (HP-LF)] to a STANDARD meal (55% carbohydrate, 30% fat, 15% protein). Experiment 1 included ten children with PWS (median age 6.63 years; BMI z 1.05); experiment 2 had seven HC (median age 12.54 years; BMI z 0.95). Blood samples were collected at baseline and at 60-minute intervals for 4 hours. Independent linear mixed models were adjusted for age, sex and BMI z-score. RESULTS Fasting and post-prandial AG and DAG concentrations are elevated in PWS children; the ratio of AG/DAG is normal. Food consumption reduced AG and DAG concentrations in both PWS and HC. GLP-1 levels were higher in PWS after the HP-LC and HP-LF meals than the STANDARD meal (P = .02-0.04). The fasting proinsulin to insulin ratio (0.08 vs 0.05) was higher in children with PWS (P = .05) than in HC. Average appetite scores in HC declined after all three meals (P = .02) but were lower after the HP-LC and HP-LF meals than the STANDARD meal. CONCLUSION Altered processing of proinsulin and increased GLP-1 secretion in children with PWS after a high protein meal intake might enhance satiety and reduce energy intake.
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Affiliation(s)
- Maha Alsaif
- Department of Agricultural, Food & Nutritional Science, University of Alberta, Edmonton, AL, Canada
| | - Mohammadreza Pakseresht
- Department of Agricultural, Food & Nutritional Science, University of Alberta, Edmonton, AL, Canada
| | - Michelle L Mackenzie
- Department of Agricultural, Food & Nutritional Science, University of Alberta, Edmonton, AL, Canada
| | - Bruce Gaylinn
- Division of Endocrinology, Department of Medicine, School of Medicine, University of Virginia, Charlottesville, VA, USA
| | - Michael O Thorner
- Division of Endocrinology, Department of Medicine, School of Medicine, University of Virginia, Charlottesville, VA, USA
| | - Michael Freemark
- Duke Molecular Physiology Institute, Duke University Medical Center, Durham, NC, USA
| | - Catherine J Field
- Department of Agricultural, Food & Nutritional Science, University of Alberta, Edmonton, AL, Canada
| | - Carla M Prado
- Department of Agricultural, Food & Nutritional Science, University of Alberta, Edmonton, AL, Canada
| | - Andrea M Haqq
- Department of Agricultural, Food & Nutritional Science, University of Alberta, Edmonton, AL, Canada
- Division of Pediatric Endocrinology, University of Alberta, Edmonton, AL, Canada
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Song L, Yuan J, Liu Y, Zhang D, Zhang C, Lin Q, Li M, Su K, Li Y, Gao G, Ma R, Dong J. Ghrelin system is involved in improvements in glucose metabolism mediated by hyperbaric oxygen treatment in a streptozotocin‑induced type 1 diabetes mouse model. Mol Med Rep 2020; 22:3767-3776. [PMID: 32901885 PMCID: PMC7533472 DOI: 10.3892/mmr.2020.11481] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 07/28/2020] [Indexed: 12/17/2022] Open
Abstract
Type 1 diabetes mellitus (T1DM) is an autoimmune disorder for which the only effective therapy is insulin replacement. Hyperbaric oxygen (HBO) therapy has demonstrated potential in improving hyperglycemia and as a treatment option for T1DM. Ghrelin and HBO have been previously reported to exert proliferative, anti-apoptotic and anti-inflammatory effects in pancreatic cells. The present study investigated the mechanism underlying HBO- and ghrelin system-mediated regulation of glucose metabolism. Male C57BL/6 mice were intraperitoneally injected with streptozotocin (STZ; 150 mg/kg) to induce T1DM before the diabetic mice were randomly assigned into the T1DM and T1DM + HBO groups. Mice in the T1DM + HBO group received HBO (1 h; 100% oxygen; 2 atmospheres absolute) daily for 2 weeks. Significantly lower blood glucose levels and food intake were observed in mice in the T1DM + HBO group. Following HBO treatment, islet β-cell area were increased whereas those of α-cell were decreased in the pancreas. In addition, greater hepatic glycogen storage in liver was observed, which coincided with higher pancreatic glucose transporter 2 (GLUT2) expression levels and reduced hepatic GLUT2 membrane trafficking. There were also substantially higher total plasma ghrelin concentrations and gastric ghrelin-O-acyl transferase (GOAT) expression levels in mice in the T1DM + HBO group. HBO treatment also abolished reductions in pancreatic GOAT expression levels in T1DM mice. Additionally, hepatic growth hormone secretagogue receptor-1a levels were found to be lower in mice in the T1DM + HBO group compared with those in the T1DM group. These results suggest that HBO administration improved glucose metabolism in a STZ-induced T1DM mouse model. The underlying mechanism involves improved insulin-release, glucose-sensing and regulation of hepatic glycogen storage, an observation that was also likely dependent on the ghrelin signalling system.
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Affiliation(s)
- Limin Song
- Department of Special Medicine, Medical College, Qingdao University, Qingdao, Shandong 266071, P.R. China
| | - Junhua Yuan
- Department of Special Medicine, Medical College, Qingdao University, Qingdao, Shandong 266071, P.R. China
| | - Yuan Liu
- Department of Special Medicine, Medical College, Qingdao University, Qingdao, Shandong 266071, P.R. China
| | - Di Zhang
- Department of Special Medicine, Medical College, Qingdao University, Qingdao, Shandong 266071, P.R. China
| | - Caishun Zhang
- Department of Special Medicine, Medical College, Qingdao University, Qingdao, Shandong 266071, P.R. China
| | - Qian Lin
- Department of Special Medicine, Medical College, Qingdao University, Qingdao, Shandong 266071, P.R. China
| | - Manwen Li
- Department of Special Medicine, Medical College, Qingdao University, Qingdao, Shandong 266071, P.R. China
| | - Kaizhen Su
- Department of Clinical Medicine, Medical College, Qingdao University, Qingdao, Shandong 266071, P.R. China
| | - Yanrun Li
- Department of Clinical Medicine, Medical College, Qingdao University, Qingdao, Shandong 266071, P.R. China
| | - Guangkai Gao
- Department of Hyperbaric Medicine, Hospital of Chinese People's Liberation Army, Qingdao, Shandong 266072, P.R. China
| | - Ruixia Ma
- Department of Nephrology, Affiliated Hospital of Qingdao University, Qingdao, Shandong 266005, P.R. China
| | - Jing Dong
- Department of Special Medicine, Medical College, Qingdao University, Qingdao, Shandong 266071, P.R. China
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11
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Tan Q, Orsso CE, Deehan EC, Triador L, Field CJ, Tun HM, Han JC, Müller TD, Haqq AM. Current and emerging therapies for managing hyperphagia and obesity in Prader-Willi syndrome: A narrative review. Obes Rev 2020; 21:e12992. [PMID: 31889409 DOI: 10.1111/obr.12992] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 12/07/2019] [Accepted: 12/09/2019] [Indexed: 12/16/2022]
Abstract
In early childhood, individuals with Prader-Willi syndrome (PWS) experience excess weight gain and severe hyperphagia with food compulsivity, which often leads to early onset morbid obesity. Effective treatments for appetite suppression and weight control are currently unavailable for PWS. Our aim to further understand the pathogenesis of PWS led us to carry out a comprehensive search of the current and emerging therapies for managing hyperphagia and extreme weight gain in PWS. A literature search was performed using PubMed and the following keywords: "PWS" AND "therapy" OR "[drug name]"; reference lists, pharmaceutical websites, and the ClinicalTrials.gov registry were also reviewed. Articles presenting data from current standard treatments in PWS and also clinical trials of pharmacological agents in the pipeline were selected. Current standard treatments include dietary restriction/modifications, exercise, and growth hormone replacement, which appear to have limited efficacy for appetite and weight control in patients with PWS. The long-term safety and effectiveness of bariatric surgery in PWS remains unknown. However, many promising pharmacotherapies are in development and, if approved, will bring much needed choices into the PWS pharmacological armamentarium. With the progress that is currently being made in our understanding of PWS, an effective treatment may not be far off.
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Affiliation(s)
- Qiming Tan
- Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada
| | - Camila E Orsso
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
| | - Edward C Deehan
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
| | - Lucila Triador
- Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada
| | - Catherine J Field
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
| | - Hein Min Tun
- HKU-Pasteur Research Pole, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, SAR, China
| | - Joan C Han
- Departments of Pediatrics and Physiology, College of Medicine, University of Tennessee Health Science Center and Children's Foundation Research Institute, Le Bonheur Children's Hospital, Memphis, Tennessee, USA
| | - Timo D Müller
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center at Helmholtz Zentrum München, Neuherberg, Germany.,Department of Pharmacology and Experimental Therapy, Institute of Experimental and Clinical Pharmacology and Toxicology, Eberhard Karls University Hospitals and Clinics, Tübingen, Germany
| | - Andrea M Haqq
- Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada.,Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
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12
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Wu TH, Chiu CC, Goh KK, Chen PY, Huang MC, Chen CH, Lu ML. Relationship between metabolic syndrome and acylated/desacylated ghrelin ratio in patients with schizophrenia under olanzapine medication. J Psychopharmacol 2020; 34:86-92. [PMID: 31692408 DOI: 10.1177/0269881119885260] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Ghrelin is a peptide hormone that mediates glucose homeostasis and lipid metabolism. Acylated ghrelin (AG) and desacylated ghrelin (DAG) are the two main forms of ghrelin, which have opposing roles in energy homeostasis. The AG/DAG ratio has been proposed to be associated with metabolic syndrome (MetS) in the general population. This study compared the relationships between MetS and ghrelin parameters in patients with schizophrenia. METHODS Patients diagnosed with schizophrenia and under olanzapine monotherapy were recruited. Fasting blood samples were collected for the analyses of metabolic and ghrelin parameters. The serum levels of total ghrelin and AG were measured by enzyme-linked immunosorbent assay kits. DAG level was calculated by subtracting the AG level from the total ghrelin level. RESULTS We recruited 151 subjects with schizophrenia, and classified them into those with MetS (n = 41) and those without MetS (n = 110). Subjects with MetS had a significantly higher AG/DAG ratio, as well as lower total ghrelin and DAG levels. There were no sex differences in ghrelin parameters. The AG/DAG ratio was significantly and positively correlated with weight, body mass index, waist circumference, insulin level, homeostasis model assessment of insulin resistance and number of MetS components. Multiple linear regression analysis indicated that the number of MetS components remained significantly associated with the AG/DAG ratio. CONCLUSIONS Our results revealed that lower AG/DAG ratios were associated with better metabolic profiles in olanzapine-treated patients with schizophrenia. These observations suggest that the balance between AG and DAG plays a crucial role in the metabolic homeostasis among patients with schizophrenia.
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Affiliation(s)
- Tzu-Hua Wu
- Department of Clinical Pharmacy, School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei, Taiwan.,Psychiatric Research Centre, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - Chih-Chiang Chiu
- Department of Psychiatry, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Department of Psychiatry, Taipei City Psychiatric Centre, Taipei City Hospital, Taipei, Taiwan
| | - Kah Kheng Goh
- Psychiatric Research Centre, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.,Department of Psychiatry, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - Po-Yu Chen
- Department of Psychiatry, Taipei City Psychiatric Centre, Taipei City Hospital, Taipei, Taiwan
| | - Ming-Chyi Huang
- Department of Psychiatry, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Department of Psychiatry, Taipei City Psychiatric Centre, Taipei City Hospital, Taipei, Taiwan
| | - Chun-Hsin Chen
- Psychiatric Research Centre, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.,Department of Psychiatry, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Department of Psychiatry, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - Mong-Liang Lu
- Psychiatric Research Centre, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.,Department of Psychiatry, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Department of Psychiatry, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
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13
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Gray SM, Page LC, Tong J. Ghrelin regulation of glucose metabolism. J Neuroendocrinol 2019; 31:e12705. [PMID: 30849212 PMCID: PMC6688917 DOI: 10.1111/jne.12705] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 03/04/2019] [Accepted: 03/05/2019] [Indexed: 12/14/2022]
Abstract
Ghrelin and its receptor, the growth hormone secretagogue receptor 1a (GHSR1a), are implicated in the regulation of glucose metabolism via direct actions in the pancreatic islet, as well as peripheral insulin-sensitive tissues and the brain. Although many studies have explored the role of ghrelin in glucose tolerance and insulin secretion, a complete mechanistic understanding remains to be clarified. This review highlights the local expression and function of ghrelin and GHSR1a in pancreatic islets and how this axis may modulate insulin secretion from pancreatic β-cells. Additionally, we discuss the effect of ghrelin on in vivo glucose metabolism in rodents and humans, as well as the metabolic circumstances under which the action of ghrelin may predominate.
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Affiliation(s)
- Sarah. M. Gray
- Duke Molecular Physiology Institute, Duke University, Durham, NC 27701
| | - Laura C. Page
- Division of Endocrinology, Department of Pediatrics, Duke University, Durham, NC 27701
| | - Jenny Tong
- Duke Molecular Physiology Institute, Duke University, Durham, NC 27701
- Division of Endocrinology, Department of Pediatrics, Duke University, Durham, NC 27701
- Division of Endocrinology, Metabolism, and Nutrition, Department of Medicine, Duke University, Durham, NC 27701
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14
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Mani BK, Shankar K, Zigman JM. Ghrelin's Relationship to Blood Glucose. Endocrinology 2019; 160:1247-1261. [PMID: 30874792 PMCID: PMC6482034 DOI: 10.1210/en.2019-00074] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 03/09/2019] [Indexed: 12/16/2022]
Abstract
Much effort has been directed at studying the orexigenic actions of administered ghrelin and the potential effects of the endogenous ghrelin system on food intake, food reward, body weight, adiposity, and energy expenditure. Although endogenous ghrelin's actions on some of these processes remain ambiguous, its glucoregulatory actions have emerged as well-recognized features during extreme metabolic conditions. The blood glucose-raising actions of ghrelin are beneficial during starvation-like conditions, defending against life-threatening falls in blood glucose, but they are seemingly detrimental in obese states and in certain monogenic forms of diabetes, contributing to hyperglycemia. Also of interest, blood glucose negatively regulates ghrelin secretion. This article reviews the literature suggesting the existence of a blood glucose-ghrelin axis and highlights the factors that mediate the glucoregulatory actions of ghrelin, especially during metabolic extremes such as starvation and diabetes.
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Affiliation(s)
- Bharath K Mani
- Division of Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
- Division of Endocrinology and Metabolism, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Kripa Shankar
- Division of Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
- Division of Endocrinology and Metabolism, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Jeffrey M Zigman
- Division of Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
- Division of Endocrinology and Metabolism, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas
- Correspondence: Jeffrey M. Zigman, MD, PhD, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390. E-mail:
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15
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Unacylated Ghrelin Improves Vascular Dysfunction and Attenuates Atherosclerosis during High-Fat Diet Consumption in Rodents. Int J Mol Sci 2019; 20:ijms20030499. [PMID: 30682769 PMCID: PMC6387360 DOI: 10.3390/ijms20030499] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 01/10/2019] [Accepted: 01/15/2019] [Indexed: 12/13/2022] Open
Abstract
Unacylated ghrelin (UnGhr) exerts several beneficial actions on vascular function. The aim of this study was to assess the effects of UnGhr on high-fat induced endothelial dysfunction and its underlying mechanisms. Thoracic aortas from transgenic mice, which were overexpressing UnGhr and being control fed either a standard control diet (CD) or a high-fat diet (HFD) for 16 weeks, were harvested and used for the assessment of vascular reactivity, endothelial nitric oxide synthase (eNOS) expression and activity, thiobarbituric acid reactive substances (TBARS) and glutathione levels, and aortic lipid accumulation by Oil Red O staining. Relaxations due to acetylcholine and to DEA-NONOate were reduced (p < 0.05) in the HFD control aortas compared to vessels from the CD animals. Overexpression of UnGhr prevented HFD-induced vascular dysfunction, while eNOS expression and activity were similar in all vessels. HFD-induced vascular oxidative stress was demonstrated by increased (p < 0.05) aortic TBARS and glutathione in wild type (Wt) mice; however, this was not seen in UnGhr mice. Moreover, increased (p < 0.05) HFD-induced lipid accumulation in vessels from Wt mice was prevented by UnGhr overexpression. In conclusion, chronic UnGhr overexpression results in improved vascular function and reduced plaque formation through decreased vascular oxidative stress, without affecting the eNOS pathway. This research may provide new insight into the mechanisms underlying the beneficial effects of UnGhr on the vascular dysfunction associated with obesity and the metabolic syndrome.
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16
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Maugham ML, Seim I, Thomas PB, Crisp GJ, Shah ET, Herington AC, Brown KA, Gregory LS, Nelson CC, Jeffery PL, Chopin LK. No effect of unacylated ghrelin administration on subcutaneous PC3 xenograft growth or metabolic parameters in a Rag1-/- mouse model of metabolic dysfunction. PLoS One 2018; 13:e0198495. [PMID: 30458004 PMCID: PMC6245673 DOI: 10.1371/journal.pone.0198495] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 11/02/2018] [Indexed: 12/12/2022] Open
Abstract
Ghrelin is a peptide hormone which, when acylated, regulates appetite, energy balance and a range of other biological processes. Ghrelin predominately circulates in its unacylated form (unacylated ghrelin; UAG). UAG has a number of functions independent of acylated ghrelin, including modulation of metabolic parameters and cancer progression. UAG has also been postulated to antagonise some of the metabolic effects of acyl-ghrelin, including its effects on glucose and insulin regulation. In this study, Rag1-/- mice with high-fat diet-induced obesity and hyperinsulinaemia were subcutaneously implanted with PC3 prostate cancer xenografts to investigate the effect of UAG treatment on metabolic parameters and xenograft growth. Daily intraperitoneal injection of 100 μg/kg UAG had no effect on xenograft tumour growth in mice fed normal rodent chow or 23% high-fat diet. UAG significantly improved glucose tolerance in host Rag1-/- mice on a high-fat diet, but did not significantly improve other metabolic parameters. We propose that UAG is not likely to be an effective treatment for prostate cancer, with or without associated metabolic syndrome.
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Affiliation(s)
- Michelle L. Maugham
- Ghrelin Research Group, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Australian Prostate Cancer Research Centre - Queensland, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Comparative and Endocrine Biology Laboratory, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Skeletal Biology and Forensic Anthropology Research Laboratory, School of Biomedical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Inge Seim
- Ghrelin Research Group, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Australian Prostate Cancer Research Centre - Queensland, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Comparative and Endocrine Biology Laboratory, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Integrative Biology Laboratory, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Patrick B. Thomas
- Ghrelin Research Group, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Australian Prostate Cancer Research Centre - Queensland, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Comparative and Endocrine Biology Laboratory, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Gabrielle J. Crisp
- Ghrelin Research Group, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Australian Prostate Cancer Research Centre - Queensland, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Comparative and Endocrine Biology Laboratory, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Esha T. Shah
- Ghrelin Research Group, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Australian Prostate Cancer Research Centre - Queensland, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Comparative and Endocrine Biology Laboratory, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Adrian C. Herington
- Ghrelin Research Group, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Australian Prostate Cancer Research Centre - Queensland, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Kristy A. Brown
- Department of Medicine, Weill Cornell Medicine, New York City, New York, United States of America
| | - Laura S. Gregory
- Skeletal Biology and Forensic Anthropology Research Laboratory, School of Biomedical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Colleen C. Nelson
- Australian Prostate Cancer Research Centre - Queensland, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Penny L. Jeffery
- Ghrelin Research Group, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Australian Prostate Cancer Research Centre - Queensland, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Comparative and Endocrine Biology Laboratory, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Lisa K. Chopin
- Ghrelin Research Group, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Australian Prostate Cancer Research Centre - Queensland, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
- Comparative and Endocrine Biology Laboratory, Translational Research Institute – Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
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17
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Sinagoga KL, McCauley HA, Múnera JO, Reynolds NA, Enriquez JR, Watson C, Yang HC, Helmrath MA, Wells JM. Deriving functional human enteroendocrine cells from pluripotent stem cells. Development 2018; 145:dev.165795. [PMID: 30143540 DOI: 10.1242/dev.165795] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 08/20/2018] [Indexed: 12/13/2022]
Abstract
Enteroendocrine cells (EECs) are a minor cell population in the intestine yet they play a major role in digestion, satiety and nutrient homeostasis. Recently developed human intestinal organoid models include EECs, but their rarity makes it difficult to study their formation and function. Here, we used the EEC-inducing property of the transcription factor NEUROG3 in human pluripotent stem cell-derived human intestinal organoids and colonic organoids to promote EEC development in vitro An 8-h pulse of NEUROG3 expression induced expression of known target transcription factors and after 7 days organoids contained up to 25% EECs in the epithelium. EECs expressed a broad array of human hormones at the mRNA and/or protein level, including motilin, somatostatin, neurotensin, secretin, substance P, serotonin, vasoactive intestinal peptide, oxyntomodulin, GLP-1 and INSL5. EECs secreted several hormones including gastric inhibitory polypeptide (GIP), ghrelin, GLP-1 and oxyntomodulin. Injection of glucose into the lumen of organoids caused an increase in both GIP secretion and K-cell number. Lastly, we observed formation of all known small intestinal EEC subtypes following transplantation and growth of human intestinal organoids in mice.
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Affiliation(s)
- Katie L Sinagoga
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229-3039, USA
| | - Heather A McCauley
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229-3039, USA
| | - Jorge O Múnera
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229-3039, USA
| | - Nichole A Reynolds
- Endocrine/Cardiovascular Division, Eli Lilly and Company, Indianapolis, IN 46285, USA
| | - Jacob R Enriquez
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229-3039, USA
| | - Carey Watson
- Division of Pediatric General and Thoracic Surgery, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229-3039, USA
| | - Hsiu-Chiung Yang
- Endocrine/Cardiovascular Division, Eli Lilly and Company, Indianapolis, IN 46285, USA
| | - Michael A Helmrath
- Division of Pediatric General and Thoracic Surgery, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229-3039, USA.,Center for Stem Cell and Organoid Medicine, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229-3039, USA
| | - James M Wells
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229-3039, USA .,Center for Stem Cell and Organoid Medicine, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229-3039, USA.,Division of Endocrinology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229-3039, USA
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18
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AZP-531, an unacylated ghrelin analog, improves food-related behavior in patients with Prader-Willi syndrome: A randomized placebo-controlled trial. PLoS One 2018; 13:e0190849. [PMID: 29320575 PMCID: PMC5761957 DOI: 10.1371/journal.pone.0190849] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 12/18/2017] [Indexed: 11/19/2022] Open
Abstract
Context and objective Prader-Willi syndrome (PWS) is characterized by early-onset hyperphagia and increased circulating levels of the orexigenic Acylated Ghrelin (AG) hormone with a relative deficit of Unacylated Ghrelin (UAG). AZP-531, a first-in-class UAG analog, was shown to inhibit the orexigenic effect of AG in animals, to improve glycemic control and decrease body weight in humans. We aimed to investigate the safety and efficacy of AZP-531 in patients with PWS for whom no approved treatment for hyperphagia is currently available. Methods and design Multi-center, randomized, double-blind, placebo-controlled trial. Forty-seven patients with genetically confirmed PWS and evidence of hyperphagia received daily subcutaneous injections of AZP-531 (3 and 4 mg for 50–70 kg and >70 kg body weight, respectively) or matching placebo for 14 days. Assessments included adverse events, vital signs, safety laboratory tests, the Hyperphagia Questionnaire (HQ), patient-reported appetite, body composition and glycemic measures. Results AZP-531 was well tolerated. There was a significant improvement with AZP-531 versus placebo in the mean total score, the 9-item score and the severity domain score of the HQ (p < .05). The highest reduction in the total and 9-item scores was observed in AZP-531 subjects with the highest hyperphagia score at baseline. Findings were supported by a reduction in appetite scores observed with AZP-531 only. Body weight did not change in both groups while a significant reduction in waist circumference and fat mass was observed only with AZP-531. AZP-531 significantly decreased post-prandial glucose levels in a baseline glucose dependent fashion. Conclusions AZP-531 may constitute a new treatment strategy to improve hyperphagia and metabolic issues in patients with PWS. These findings support further investigation in longer-term clinical trials.
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19
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Sominsky L, Goularte JF, Andrews ZB, Spencer SJ. Acylated Ghrelin Supports the Ovarian Transcriptome and Follicles in the Mouse: Implications for Fertility. Front Endocrinol (Lausanne) 2018; 9:815. [PMID: 30697193 PMCID: PMC6340924 DOI: 10.3389/fendo.2018.00815] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 12/27/2018] [Indexed: 12/16/2022] Open
Abstract
Ghrelin, an orexigenic gut-derived peptide, is gaining increasing attention due to its multifaceted role in a number of physiological functions, including reproduction. Ghrelin exists in circulation primarily as des-acylated and acylated ghrelin. Des-acyl ghrelin, until recently considered to be an inactive form of ghrelin, is now known to have independent physiological functionality. However, the relative contribution of acyl and des-acyl ghrelin to reproductive development and function is currently unknown. Here we used ghrelin-O-acyltransferase (GOAT) knockout (KO) mice that have no measurable levels of endogenous acyl ghrelin and chronically high levels of des-acyl ghrelin, to characterize how the developmental and life-long absence of acyl ghrelin affects ovarian development and reproductive capacity. We combined the assessment of markers of reproductive maturity and the capacity to breed with measures of ovarian morphometry, as well as with ovarian RNA sequencing analysis. Our data show that while GOAT KO mice retain the capacity to breed in young adulthood, there is a diminished number of ovarian follicles (per mm3) in the juvenile and adult ovaries, due to a significant reduction in the number of small follicles, particularly the primordial follicles. We also show pronounced specific changes in the ovarian transcriptome in the juvenile GOAT KO ovary, indicative of a potential for premature ovarian development. Collectively, these findings indicate that an absence of acyl ghrelin does not prevent reproductive success but that appropriate levels of acyl and des-acyl ghrelin may be necessary for optimal ovarian maturation.
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Affiliation(s)
- Luba Sominsky
- School of Health and Biomedical Sciences, RMIT University, Melbourne, VIC, Australia
- *Correspondence: Luba Sominsky
| | - Jeferson F. Goularte
- Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, VIC, Australia
| | - Zane B. Andrews
- Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, VIC, Australia
| | - Sarah J. Spencer
- School of Health and Biomedical Sciences, RMIT University, Melbourne, VIC, Australia
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20
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Sominsky L, Hodgson DM, McLaughlin EA, Smith R, Wall HM, Spencer SJ. Linking Stress and Infertility: A Novel Role for Ghrelin. Endocr Rev 2017; 38:432-467. [PMID: 28938425 DOI: 10.1210/er.2016-1133] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 07/24/2017] [Indexed: 12/23/2022]
Abstract
Infertility affects a remarkable one in four couples in developing countries. Psychological stress is a ubiquitous facet of life, and although stress affects us all at some point, prolonged or unmanageable stress may become harmful for some individuals, negatively impacting on their health, including fertility. For instance, women who struggle to conceive are twice as likely to suffer from emotional distress than fertile women. Assisted reproductive technology treatments place an additional physical, emotional, and financial burden of stress, particularly on women, who are often exposed to invasive techniques associated with treatment. Stress-reduction interventions can reduce negative affect and in some cases to improve in vitro fertilization outcomes. Although it has been well-established that stress negatively affects fertility in animal models, human research remains inconsistent due to individual differences and methodological flaws. Attempts to isolate single causal links between stress and infertility have not yet been successful due to their multifaceted etiologies. In this review, we will discuss the current literature in the field of stress-induced reproductive dysfunction based on animal and human models, and introduce a recently unexplored link between stress and infertility, the gut-derived hormone, ghrelin. We also present evidence from recent seminal studies demonstrating that ghrelin has a principal role in the stress response and reward processing, as well as in regulating reproductive function, and that these roles are tightly interlinked. Collectively, these data support the hypothesis that stress may negatively impact upon fertility at least in part by stimulating a dysregulation in ghrelin signaling.
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Affiliation(s)
- Luba Sominsky
- School of Health and Biomedical Sciences, RMIT University, Melbourne, Victoria 3083, Australia
| | - Deborah M Hodgson
- School of Psychology, Faculty of Science and IT, The University of Newcastle, New South Wales 2308, Australia
| | - Eileen A McLaughlin
- School of Biological Sciences, Faculty of Science, The University of Auckland, Auckland 1010, New Zealand.,School of Environmental & Life Sciences, Faculty of Science and IT, The University of Newcastle, New South Wales 2308, Australia
| | - Roger Smith
- Mothers and Babies Research Centre, Hunter Medical Research Institute, Lookout Road, New Lambton Heights, New South Wales 2305, Australia.,Priority Research Centre in Reproductive Science, The University of Newcastle, New South Wales 2308, Australia
| | - Hannah M Wall
- School of Health and Biomedical Sciences, RMIT University, Melbourne, Victoria 3083, Australia
| | - Sarah J Spencer
- School of Health and Biomedical Sciences, RMIT University, Melbourne, Victoria 3083, Australia
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21
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Central Modulation of Neuroinflammation by Neuropeptides and Energy-Sensing Hormones during Obesity. BIOMED RESEARCH INTERNATIONAL 2017; 2017:7949582. [PMID: 28913358 PMCID: PMC5587954 DOI: 10.1155/2017/7949582] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 07/19/2017] [Accepted: 07/24/2017] [Indexed: 02/06/2023]
Abstract
Central nervous system (CNS) senses energy homeostasis by integrating both peripheral and autonomic signals and responding to them by neurotransmitters and neuropeptides release. Although it is previously considered an immunologically privileged organ, we now know that this is not so. Cells belonging to the immune system, such as B and T lymphocytes, can be recruited into the CNS to face damage or infection, in addition to possessing resident immunological cells, called microglia. In this way, positive energy balance during obesity promotes an inflammatory state in the CNS. Saturated fatty acids from the diet have been pointed out as powerful candidates to trigger immune response in peripheral system and in the CNS. However, how central immunity communicates to peripheral immune response remains to be clarified. Recently there has been a great interest in the neuropeptides, POMC derived peptides, ghrelin, and leptin, due to their capacity to suppress or induce inflammatory responses in the brain, respectively. These may be potential candidates to treat different pathologies associated with autoimmunity and inflammation. In this review, we will discuss the role of lipotoxicity associated with positive energy balance during obesity in proinflammatory response in microglia, B and T lymphocytes, and its modulation by neuropeptides.
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22
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Muhammad A, Delhanty PJD, Huisman M, Visser JA, Jan van der Lelij A, Neggers SJCMM. The Acylated/Unacylated Ghrelin Ratio Is Similar in Patients With Acromegaly During Different Treatment Regimens. J Clin Endocrinol Metab 2017; 102:2425-2432. [PMID: 28402548 DOI: 10.1210/jc.2017-00147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 04/06/2017] [Indexed: 01/08/2023]
Abstract
BACKGROUND Data on plasma acylated ghrelin (AG) and unacylated ghrelin (UAG) levels in acromegaly are limited. High AG/UAG ratios are linked with type 2 diabetes, obesity, and hyperphagia (e.g., in Prader-Willi syndrome). OBJECTIVE To assess fasting plasma AG and UAG levels, and the AG/UAG ratio in acromegaly patients receiving combination treatment of long-acting somatostatin analogs (LA-SSAs) and pegvisomant (PEGV; n = 60). We used as controls acromegaly patients whose disease was controlled with PEGV monotherapy and medically naïve patients with active acromegaly. METHODS Fasting venous blood samples were collected and directly stabilized to inhibit deacylation of AG. Plasma AG and UAG levels were determined by double-antibody sandwich enzyme immunoassay, and the AG/UAG ratio was calculated. RESULTS Plasma AG and UAG levels were significantly lower in patients with acromegaly receiving combination treatment [median, interquartile range (IQR): AG: 8.5 pg/mL, 2.9 to 21.1 pg/mL; UAG: 26.9 pg/mL, 11.2 to 42.1 pg/mL] compared with patients using PEGV alone [AG: 60.5 pg/mL (IQR, 58.8 to 77.4 pg/mL); UAG: 153.7 pg/mL (IQR, 127.3 to 196.0 pg/mL)] and medically naïve patients with acromegaly [AG: 24.0 pg/mL (IQR, 12.6 to 49.7 pg/mL); UAG: 56.3 pg/mL (IQR, 43.4 to 61.5 pg/mL)]. However, AG/UAG ratios were similar in all groups. CONCLUSIONS Although plasma AG and UAG are suppressed during combination treatment with LA-SSAs and PEGV, the AG/UAG ratio remained similar. This shows that SSAs decrease both AG and UAG levels, which suggests that they do not alter metabolism significantly in acromegaly patients.
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Affiliation(s)
- Ammar Muhammad
- Department of Internal Medicine, Section of Endocrinology, Erasmus University MC, 3000 CA Rotterdam, The Netherlands
| | - Patric J D Delhanty
- Department of Internal Medicine, Section of Endocrinology, Erasmus University MC, 3000 CA Rotterdam, The Netherlands
| | - Martin Huisman
- Department of Internal Medicine, Section of Endocrinology, Erasmus University MC, 3000 CA Rotterdam, The Netherlands
| | - Jenny A Visser
- Department of Internal Medicine, Section of Endocrinology, Erasmus University MC, 3000 CA Rotterdam, The Netherlands
| | - Aart Jan van der Lelij
- Department of Internal Medicine, Section of Endocrinology, Erasmus University MC, 3000 CA Rotterdam, The Netherlands
| | - Sebastian J C M M Neggers
- Department of Internal Medicine, Section of Endocrinology, Erasmus University MC, 3000 CA Rotterdam, The Netherlands
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23
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Reano S, Angelino E, Ferrara M, Malacarne V, Sustova H, Sabry O, Agosti E, Clerici S, Ruozi G, Zentilin L, Prodam F, Geuna S, Giacca M, Graziani A, Filigheddu N. Unacylated Ghrelin Enhances Satellite Cell Function and Relieves the Dystrophic Phenotype in Duchenne Muscular Dystrophy mdx Model. Stem Cells 2017; 35:1733-1746. [PMID: 28436144 DOI: 10.1002/stem.2632] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 02/28/2017] [Accepted: 04/06/2017] [Indexed: 12/17/2022]
Abstract
Muscle regeneration depends on satellite cells (SCs), quiescent precursors that, in consequence of injury or in pathological states such as muscular dystrophies, activate, proliferate, and differentiate to repair the damaged tissue. A subset of SCs undergoes self-renewal, thus preserving the SC pool and its regenerative potential. Unacylated ghrelin (UnAG) is a circulating hormone that protects muscle from atrophy, promotes myoblast differentiation, and enhances ischemia-induced muscle regeneration. Here we show that UnAG increases SC activity and stimulates Par polarity complex/p38-mediated asymmetric division, fostering both SC self-renewal and myoblast differentiation. Because of those activities on different steps of muscle regeneration, we hypothesized a beneficial effect of UnAG in mdx dystrophic mice, in which the absence of dystrophin leads to chronic muscle degeneration, defective muscle regeneration, fibrosis, and, at later stages of the pathology, SC pool exhaustion. Upregulation of UnAG levels in mdx mice reduces muscle degeneration, improves muscle function, and increases dystrophin-null SC self-renewal, maintaining the SC pool. Our results suggest that UnAG has significant therapeutic potential for preserving the muscles in dystrophies. Stem Cells 2017;35:1733-1746.
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Affiliation(s)
- Simone Reano
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy and Istituto Interuniversitario di Miologia (IIM)
| | - Elia Angelino
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy and Istituto Interuniversitario di Miologia (IIM)
| | - Michele Ferrara
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy and Istituto Interuniversitario di Miologia (IIM)
| | - Valeria Malacarne
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy and Istituto Interuniversitario di Miologia (IIM)
| | - Hana Sustova
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy and Istituto Interuniversitario di Miologia (IIM)
| | - Omar Sabry
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy and Istituto Interuniversitario di Miologia (IIM)
| | - Emanuela Agosti
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy and Istituto Interuniversitario di Miologia (IIM)
| | - Sara Clerici
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy and Istituto Interuniversitario di Miologia (IIM)
| | - Giulia Ruozi
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy
| | - Lorena Zentilin
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy
| | - Flavia Prodam
- Department of Health Sciences, University of Piemonte Orientale, Novara, Italy
| | - Stefano Geuna
- Department of Clinical and Biological Sciences, University of Torino and Neuroscience Institute Cavalieri Ottolenghi (NICO), Orbassano (TO), Italy
| | - Mauro Giacca
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy
| | - Andrea Graziani
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy and Istituto Interuniversitario di Miologia (IIM)
| | - Nicoletta Filigheddu
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy and Istituto Interuniversitario di Miologia (IIM)
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24
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Colldén G, Tschöp MH, Müller TD. Therapeutic Potential of Targeting the Ghrelin Pathway. Int J Mol Sci 2017; 18:ijms18040798. [PMID: 28398233 PMCID: PMC5412382 DOI: 10.3390/ijms18040798] [Citation(s) in RCA: 101] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 04/03/2017] [Accepted: 04/06/2017] [Indexed: 02/07/2023] Open
Abstract
Ghrelin was discovered in 1999 as the endogenous ligand of the growth-hormone secretagogue receptor 1a (GHSR1a). Since then, ghrelin has been found to exert a plethora of physiological effects that go far beyond its initial characterization as a growth hormone (GH) secretagogue. Among the numerous well-established effects of ghrelin are the stimulation of appetite and lipid accumulation, the modulation of immunity and inflammation, the stimulation of gastric motility, the improvement of cardiac performance, the modulation of stress, anxiety, taste sensation and reward-seeking behavior, as well as the regulation of glucose metabolism and thermogenesis. Due to a variety of beneficial effects on systems’ metabolism, pharmacological targeting of the endogenous ghrelin system is widely considered a valuable approach to treat metabolic complications, such as chronic inflammation, gastroparesis or cancer-associated anorexia and cachexia. The aim of this review is to discuss and highlight the broad pharmacological potential of ghrelin pathway modulation for the treatment of anorexia, cachexia, sarcopenia, cardiopathy, neurodegenerative disorders, renal and pulmonary disease, gastrointestinal (GI) disorders, inflammatory disorders and metabolic syndrome.
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Affiliation(s)
- Gustav Colldén
- Institute for Diabetes and Obesity & Helmholtz Diabetes Center, Helmholtz Zentrum München German Research Center for Environmental Health (GmbH), 85764 Neuherberg, Germany.
| | - Matthias H Tschöp
- Institute for Diabetes and Obesity & Helmholtz Diabetes Center, Helmholtz Zentrum München German Research Center for Environmental Health (GmbH), 85764 Neuherberg, Germany.
- Division of Metabolic Diseases, Department of Medicine, Technische Universität München, 80333 Munich, Germany.
| | - Timo D Müller
- Institute for Diabetes and Obesity & Helmholtz Diabetes Center, Helmholtz Zentrum München German Research Center for Environmental Health (GmbH), 85764 Neuherberg, Germany.
- Institute for Diabetes and Obesity (IDO), Business Campus Garching-Hochbrück, Parkring 13, 85748 Garching, Germany.
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25
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Labarthe A, Tolle V. [Ghrelin: a gastric hormone at the crossroad between growth and appetite regulation]. Biol Aujourdhui 2017; 210:237-257. [PMID: 28327282 DOI: 10.1051/jbio/2016027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Indexed: 06/06/2023]
Abstract
Ghrelin is a 28 amino acid peptide hormone synthesized within the gastrointestinal tract. Initially identified as the endogenous ligand of the GHS-R1a (Growth Hormone Secretagogue Receptor 1a), ghrelin is a powerful stimulator of growth hormone (GH) secretion. At the crossroad between nutrition, growth and long-term energy metabolism, ghrelin also plays a unique role as the first identified gastric hormone increasing appetite and adiposity. However, the role of the ghrelin/GHS-R system in the physiology of growth, feeding behaviour and energy homeostasis needs to be better understood. Utilization of pharmacological tools and complementary animal models with deficiency in preproghrelin, ghrelin-O-acyl-transferase (GOAT - the enzyme that acylates ghrelin -) or GHS-R in situations of chronic undernutrition or high fat diet gives a more precise overview of the role of ghrelin in the pathophysiology of eating and metabolic disorders.
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26
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Aghdam Shahryar H, Lotfi A. Effect of Ghrelin Administration on Serum Corticostrone, T3, T4 and Some Biochemical Indices in the Turkey (Meleagridis gallopova). Int J Pept Res Ther 2017. [DOI: 10.1007/s10989-017-9588-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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27
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Vestergaard ET, Jessen N, Møller N, Jørgensen JOL. Acyl Ghrelin Induces Insulin Resistance Independently of GH, Cortisol, and Free Fatty Acids. Sci Rep 2017; 7:42706. [PMID: 28198428 PMCID: PMC5309923 DOI: 10.1038/srep42706] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 01/17/2017] [Indexed: 02/05/2023] Open
Abstract
Ghrelin produced in the gut stimulates GH and ACTH secretion from the pituitary and also stimulates appetite and gastric emptying. We have shown that ghrelin also induces insulin resistance via GH-independent mechanisms, but it is unknown if this effect depends on ambient fatty acid (FFA) levels. We investigated the impact of ghrelin and pharmacological antilipolysis (acipimox) on insulin sensitivity and substrate metabolism in 8 adult hypopituitary patients on stable replacement with GH and hydrocortisone using a 2 × 2 factorial design: Ghrelin infusion, saline infusion, ghrelin plus short-term acipimox, and acipimox alone. Peripheral and hepatic insulin sensitivity was determined with a hyperinsulinemic euglycemic clamp in combination with a glucose tracer infusion. Insulin signaling was assayed in muscle biopsies. Peripheral insulin sensitivity was reduced by ghrelin independently of ambient FFA concentrations and was increased by acipimox independently of ghrelin. Hepatic insulin sensitivity was increased by acipimox. Insulin signaling pathways in skeletal muscle were not consistently regulated by ghrelin. Our data demonstrate that ghrelin induces peripheral insulin resistance independently of GH, cortisol, and FFA. The molecular mechanisms remain elusive, but we speculate that ghrelin is a hitherto unrecognized direct regulator of substrate metabolism. We also suggest that acipimox per se improves hepatic insulin sensitivity.
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Affiliation(s)
- Esben T Vestergaard
- Medical Research Laboratory, Aarhus University, Nørrebrogade 44 building 3B, 8000 Aarhus C, Denmark.,Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Nørrebrogade 44 building 2A, 8000 Aarhus C, Denmark.,Department of Pediatrics, Randers Regional Hospital, Randers 8930 Denmark
| | - Niels Jessen
- Medical Research Laboratory, Aarhus University, Nørrebrogade 44 building 3B, 8000 Aarhus C, Denmark.,Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Nørrebrogade 44 building 2A, 8000 Aarhus C, Denmark.,Research Laboratory for Biochemical Pathology, Department of Clinical Medicine, Aarhus University Hospital, Nørrebrogade 44 building 3A, 8000 Aarhus C, Denmark
| | - Niels Møller
- Medical Research Laboratory, Aarhus University, Nørrebrogade 44 building 3B, 8000 Aarhus C, Denmark.,Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Nørrebrogade 44 building 2A, 8000 Aarhus C, Denmark
| | - Jens Otto Lunde Jørgensen
- Medical Research Laboratory, Aarhus University, Nørrebrogade 44 building 3B, 8000 Aarhus C, Denmark.,Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Nørrebrogade 44 building 2A, 8000 Aarhus C, Denmark
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28
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Sominsky L, Ziko I, Nguyen TX, Andrews ZB, Spencer SJ. Early life disruption to the ghrelin system with over-eating is resolved in adulthood in male rats. Neuropharmacology 2017; 113:21-30. [DOI: 10.1016/j.neuropharm.2016.09.023] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 09/21/2016] [Accepted: 09/22/2016] [Indexed: 12/11/2022]
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29
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Özcan B, Leenen PJM, Delhanty PJD, Baldéon-Rojas LY, Neggers SJ, van der Lely AJ. Unacylated ghrelin modulates circulating angiogenic cell number in insulin-resistant states. Diabetol Metab Syndr 2017; 9:43. [PMID: 28572856 PMCID: PMC5452348 DOI: 10.1186/s13098-017-0239-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 05/17/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Type 2 diabetes (T2D) is associated with reduced numbers and impaired function of circulating angiogenic cells (CAC) which contributes to the progression of atherosclerosis and microvascular disease. Previous studies suggest that short-term infusion of unacylated ghrelin (UAG) normalizes CAC number in patients with T2D. To determine dose-dependent effects of short-term infusion of UAG in T2D patients using a cross-over model, and of long-term infusion of UAG in obese mice, on differentiation of monocyte progenitors into CAC. METHODS Eight overweight T2D patients were infused overnight with 3 and 10 µg/kg/h of UAG in a double-blind, placebo-controlled cross-over study. To assess the effects of long-term UAG treatment, obese mice were infused with UAG for 4 weeks. Monocyte progenitors were assessed for their ability to differentiate into CAC in vitro. RESULTS In T2D patients, UAG treatment caused a reduction in differentiation of CAC, dependent on UAG dose and differentiation method. However, mice treated with UAG showed a significant increase in differentiation of bone marrow progenitors into CAC. CONCLUSION UAG causes a minor suppressive effect on CAC development after short-term treatment in humans, but experiments in mice suggest that long-term treatment has beneficial effects on CAC formation. The Netherlands Trial Register: TC=2487.
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Affiliation(s)
- Behiye Özcan
- Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands
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30
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Unacylated ghrelin analog prevents myocardial reperfusion injury independently of permeability transition pore. Basic Res Cardiol 2016; 112:4. [PMID: 27995363 DOI: 10.1007/s00395-016-0595-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 12/09/2016] [Indexed: 02/06/2023]
Abstract
Reperfusion injury is responsible for an important part of myocardial infarct establishment due notably to triggering cardiomyocytes death at the first minutes of reperfusion. AZP-531 is an optimized analog of unacylated ghrelin currently in clinical development in several metabolic diseases. We investigated a potential cardioprotective effect of AZP-531 in ischemia/reperfusion (IR) and the molecular underlying mechanism(s) involved in this protection. In vivo postconditioning with AZP-531 in C57BL6 mouse IR model decreased infarct size. Western blot analysis on areas at risk from the different mouse groups showed that AZP-531 activates Akt, ERK1-2 as well as S6 and 4EBP1, mTORC1 effectors. We also showed an inhibition of caspase 3 cleavage and Bax translocation to the mitochondria. AZP-531 also stimulated the expression of antioxidants and was capable of decreasing mitochondrial H2O2 production, contributing to the reduction of ROS accumulation. AZP-531 exhibits cardioprotective effect when administrated for postconditioning in C57BL6 mouse IR model. Treatment with AZP-531 rescued the myocardium from cell death at early reperfusion by stimulating protein synthesis, inhibiting Bax/caspase 3-induced apoptosis as well as ROS accumulation and oxidative stress-induced necrosis. AZP-531 may prove useful in the treatment of IR injury.
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31
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Hassouna R, Labarthe A, Tolle V. Hypothalamic regulation of body growth and appetite by ghrelin-derived peptides during balanced nutrition or undernutrition. Mol Cell Endocrinol 2016; 438:42-51. [PMID: 27693419 DOI: 10.1016/j.mce.2016.09.027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 09/25/2016] [Accepted: 09/26/2016] [Indexed: 12/16/2022]
Abstract
Among the gastrointestinal hormones that regulate food intake and energy homeostasis, ghrelin plays a unique role as the first one identified to increases appetite and stimulate GH secretion. This review highlights the latest mechanism by which ghrelin modulates body growth, appetite and energy metabolism by exploring pharmacological actions of the hormone and consequences of genetic or pharmacological blockade of the ghrelin/GHS-R (Growth Hormone Secretagogue Receptor) system on physiological responses in specific nutritional situations. Within the hypothalamus, novel mechanisms of action of this hormone involve its interaction with other ghrelin-derived peptides, such as desacyl ghrelin and obestatin, which are thought to act as functional ghrelin antagonists, and possible modulation of the GHS-R with other G-protein coupled receptors. During chronic undernutrition such as anorexia nervosa, variations of ghrelin-derived peptides may be an adaptative metabolic response to maintain normal glycemic control. Interestingly, some of ghrelin's metabolic actions are thought to be relayed through modulation of GH, an anabolic and hyperglycemic agent.
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Affiliation(s)
- Rim Hassouna
- UMR-S 894 INSERM, Centre de Psychiatrie et Neurosciences, Université Paris Descartes, Sorbonne Paris Cité, 2 ter rue d'Alésia, 75014, Paris, France; Naomi Berrie Diabetes Center, Department of Pediatrics, Columbia University Medical Center, New York, NY, 10032, USA
| | - Alexandra Labarthe
- UMR-S 894 INSERM, Centre de Psychiatrie et Neurosciences, Université Paris Descartes, Sorbonne Paris Cité, 2 ter rue d'Alésia, 75014, Paris, France
| | - Virginie Tolle
- UMR-S 894 INSERM, Centre de Psychiatrie et Neurosciences, Université Paris Descartes, Sorbonne Paris Cité, 2 ter rue d'Alésia, 75014, Paris, France.
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32
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McGovern-Gooch KR, Rodrigues T, Darling JE, Sieburg MA, Abizaid A, Hougland JL. Ghrelin Octanoylation Is Completely Stabilized in Biological Samples by Alkyl Fluorophosphonates. Endocrinology 2016; 157:4330-4338. [PMID: 27623288 DOI: 10.1210/en.2016-1657] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Ghrelin is a peptide hormone involved in multiple physiological processes related to energy homeostasis. This hormone features a unique posttranslational serine octanoylation modification catalyzed by the enzyme ghrelin O-acyltransferase, with serine octanoylation essential for ghrelin to bind and activate its cognate receptor. Ghrelin deacylation rapidly occurs in circulation, with both ghrelin and desacyl ghrelin playing important roles in biological signaling. Understanding the regulation and physiological impact of ghrelin signaling requires the ability to rapidly protect ghrelin from deacylation in biological samples such as blood serum or cell lysates to preserve the relative concentrations of ghrelin and desacyl ghrelin. In in vitro ghrelin O-acyltransferase activity assays using insect microsomal protein fractions and mammalian cell lysate and blood serum, we demonstrate that alkyl fluorophosphonate treatment provides rapid, complete, and long-lasting protection of ghrelin acylation against serine ester hydrolysis without interference in enzyme assay or ELISA analysis. Our results support alkyl fluorophosphonate treatment as a general tool for stabilizing ghrelin and improving measurement of ghrelin and desacyl ghrelin concentrations in biochemical and clinical investigations and suggest current estimates for active ghrelin concentration and the ghrelin to desacyl ghrelin ratio in circulation may underestimate in vivo conditions.
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Affiliation(s)
- Kayleigh R McGovern-Gooch
- Department of Chemistry (K.R.M.-G., J.E.D., M.A.S., J.L.H.), Syracuse University, Syracuse, New York 13244; and Department of Neuroscience (T.R., A.A.), Carleton University, Ottawa, Ontario, Canada K1S5B6
| | - Trevor Rodrigues
- Department of Chemistry (K.R.M.-G., J.E.D., M.A.S., J.L.H.), Syracuse University, Syracuse, New York 13244; and Department of Neuroscience (T.R., A.A.), Carleton University, Ottawa, Ontario, Canada K1S5B6
| | - Joseph E Darling
- Department of Chemistry (K.R.M.-G., J.E.D., M.A.S., J.L.H.), Syracuse University, Syracuse, New York 13244; and Department of Neuroscience (T.R., A.A.), Carleton University, Ottawa, Ontario, Canada K1S5B6
| | - Michelle A Sieburg
- Department of Chemistry (K.R.M.-G., J.E.D., M.A.S., J.L.H.), Syracuse University, Syracuse, New York 13244; and Department of Neuroscience (T.R., A.A.), Carleton University, Ottawa, Ontario, Canada K1S5B6
| | - Alfonso Abizaid
- Department of Chemistry (K.R.M.-G., J.E.D., M.A.S., J.L.H.), Syracuse University, Syracuse, New York 13244; and Department of Neuroscience (T.R., A.A.), Carleton University, Ottawa, Ontario, Canada K1S5B6
| | - James L Hougland
- Department of Chemistry (K.R.M.-G., J.E.D., M.A.S., J.L.H.), Syracuse University, Syracuse, New York 13244; and Department of Neuroscience (T.R., A.A.), Carleton University, Ottawa, Ontario, Canada K1S5B6
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33
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Kuppens RJ, Delhanty PJD, Huisman TM, van der Lely AJ, Hokken-Koelega ACS. Acylated and unacylated ghrelin during OGTT in Prader-Willi syndrome: support for normal response to food intake. Clin Endocrinol (Oxf) 2016; 85:488-94. [PMID: 26850227 DOI: 10.1111/cen.13036] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 12/20/2015] [Accepted: 02/02/2016] [Indexed: 01/13/2023]
Abstract
BACKGROUND Prader-Willi syndrome (PWS) is characterized by hyperphagia with impaired satiety. PWS patients have very high acylated ghrelin (AG) with normal unacylated ghrelin (UAG) levels, resulting in an elevated AG/UAG ratio, suggesting an intrinsic defect in the ghrelin regulation. Normally, food intake induces satiety and a drop in AG and UAG levels, but it is unknown if these levels also decline in PWS. OBJECTIVE To evaluate whether the high AG levels in PWS decline in response to glucose intake during an oral glucose tolerance test (OGTT), and to investigate the effects of growth hormone (GH) treatment on this response. METHOD Serum levels of AG, UAG and AG/UAG ratio during an OGTT were determined in 24 GH-treated patients with PWS (median age 19·0, range 14·2-25·9 years) and in 10 GH-stop patients (of whom five were in GH-treated group; 18·5, 14·5-20·3 years). RESULTS In GH-treated and GH-stop young adults with PWS, there was a sharp decline of AG levels and a decrease of UAG levels in the first 30 min after the glucose load, which resulted in a lower AG/UAG ratio. GH-treated patients had significantly lower AG levels than GH-stop patients at baseline and during the OGTT. All UAG levels and AG/UAG ratios were lower in the GH-treated patients, although not significantly. CONCLUSIONS In young adults with PWS, an oral glucose load significantly reduces AG and UAG levels, suggesting normal regulation of the ghrelin axis by food intake. GH treatment results in lower AG levels at baseline and during OGTT, suggesting a more favourable metabolic profile. Our findings might suggest that the impaired satiety is not the result of an abnormal response of the orexigenic ghrelin to food intake.
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Affiliation(s)
- R J Kuppens
- Dutch Growth Research Foundation, Rotterdam, The Netherlands
- Subdivision of Endocrinology, Department of Pediatrics, Erasmus University Medical Center-Sophia Children's Hospital, Rotterdam, The Netherlands
| | - P J D Delhanty
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - T M Huisman
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - A J van der Lely
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - A C S Hokken-Koelega
- Dutch Growth Research Foundation, Rotterdam, The Netherlands
- Subdivision of Endocrinology, Department of Pediatrics, Erasmus University Medical Center-Sophia Children's Hospital, Rotterdam, The Netherlands
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Allas S, Delale T, Ngo N, Julien M, Sahakian P, Ritter J, Abribat T, van der Lely AJ. Safety, tolerability, pharmacokinetics and pharmacodynamics of AZP-531, a first-in-class analogue of unacylated ghrelin, in healthy and overweight/obese subjects and subjects with type 2 diabetes. Diabetes Obes Metab 2016; 18:868-74. [PMID: 27063928 DOI: 10.1111/dom.12675] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Revised: 04/05/2016] [Accepted: 02/24/2016] [Indexed: 01/05/2023]
Abstract
AIM To explore the safety, pharmacokinetics and pharmacodynamics in humans of the unacylated ghrelin analogue AZP-531, designed to improve glycaemic control and reduce weight. METHODS Assessments, including glucose measurements, were performed in a three-part randomized study. In Part A, healthy subjects [n = 44, age 18-50 years, body mass index (BMI) 20-28 kg/m(2) ] received a single subcutaneous dose of 0.3, 3, 15, 30, 60 or 120 µg/kg AZP-531 or placebo. In Part B, overweight/obese subjects (n = 32, age 18-65 years, BMI 28-38 kg/m(2) ) and in Part C, patients with type 2 diabetes [T2D; n = 36, age 18-65 years, BMI 20-40 kg/m(2) , glycated haemoglobin (HbA1c) 7-10%] received AZP-531 or placebo for 14 days (daily doses of 3, 15, 30 or 60 µg/kg and 15, 2 × 30 or 60 µg/kg, respectively). RESULTS AZP-531 was well tolerated. Single- and multiple-dose pharmokinetic variables were similar. Maximum AZP-531 concentrations were typically reached at 1 h post-dose. Observed maximum concentration (Cmax ) and area under the curve were dose-proportional. The mean terminal half-life (t1/2 ) was 2-3 h. In Part B, AZP-531 doses of ≥15 µg/kg significantly improved glucose concentrations, without increasing insulin levels, suggesting an insulin-sensitizing effect. AZP-531 decreased mean body weight by 2.6 kg (vs 0.8 kg for placebo). In Part C, glucose variables improved in all groups, including placebo, suggesting a study effect in uncontrolled patients at baseline. Notwithstanding, AZP-531 60 µg/kg reduced HbA1c by 0.4% (vs 0.2% for placebo) and body weight by 2.1 kg (vs 1.3 kg for placebo). CONCLUSIONS AZP-531 was well tolerated in this first-in-human study. Its pharmacokinetic profile, suitable for once-daily dosing, and metabolic effects support further clinical development for T2D.
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Affiliation(s)
- S Allas
- Alizé Pharma, Ecully, France
| | | | - N Ngo
- Quintiles Early Clinical Development PK Department, Overland Park, KS, USA
| | | | | | - J Ritter
- Phase 1 Quintiles Unit, London, UK
| | | | - A J van der Lely
- Department of Medicine, Erasmus University Medical Centre, Rotterdam, The Netherlands
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González-Domínguez MI, Lazo-de-la-Vega-Monroy ML, Zaina S, Sabanero M, Daza-Benítez L, Malacara JM, Barbosa-Sabanero G. Association of cord blood des-acyl ghrelin with birth weight, and placental GHS-R1 receptor expression in SGA, AGA, and LGA newborns. Endocrine 2016; 53:182-91. [PMID: 26754660 DOI: 10.1007/s12020-015-0833-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 12/14/2015] [Indexed: 11/29/2022]
Abstract
Although ghrelin in cord blood has been associated to birth weight, its role in fetal and postnatal growth has not been elucidated. The aim of this study was to analyze total ghrelin, acyl ghrelin (AG), and des-acyl ghrelin (DAG) in cord blood of newborns with idiopathic birth weight alterations, and to evaluate protein expression of placental GHS-R1, in order to investigate their correlation with birth weight and placental weight. We performed a cross-sectional comparative study in umbilical cord blood and placentas from healthy mothers of SGA, AGA, and LGA (small, adequate and large for gestational age) term newborns (n = 20 per group). Cord blood total ghrelin, AG, and DAG were measured by ELISA, and placental GHS-R1 expression was evaluated by Western blot. Cord blood DAG was higher in SGA compared to AGA newborns (902.1 ± 109.1 and 597.4 ± 58.2 pg/ml, respectively, p = 0.01) while LGA and AGA showed similar values (627.2 ± 76.4 pg/ml for LGA, p = 0.80). DAG negatively correlated with birthweight (r = -0.31, p = 0.02) and placental weight (r = -0.33, p = 0.02). No differences in AG or total ghrelin were found. GHS-R1 protein in placenta was not differentially expressed among SGA, AGA, and LGA. Our results suggest a role of DAG in intrauterine growth. Further studies are needed in order to elucidate the mechanisms by which DAG participates in fetal growth.
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Affiliation(s)
- Martha I González-Domínguez
- Medical Sciences Department, Health Sciences Division, University of Guanajuato, Leon Campus. 20 de Enero No. 929 Col. Obregon, 37320, Leon, Guanajuato, Mexico
| | - Maria-Luisa Lazo-de-la-Vega-Monroy
- Medical Sciences Department, Health Sciences Division, University of Guanajuato, Leon Campus. 20 de Enero No. 929 Col. Obregon, 37320, Leon, Guanajuato, Mexico
| | - Silvio Zaina
- Medical Sciences Department, Health Sciences Division, University of Guanajuato, Leon Campus. 20 de Enero No. 929 Col. Obregon, 37320, Leon, Guanajuato, Mexico
| | - Myrna Sabanero
- Biology Department, Natural and Exact Sciences Division, University of Guanajuato, Guanajuato Campus, Guanajuato, Mexico
| | | | - Juan Manuel Malacara
- Medical Sciences Department, Health Sciences Division, University of Guanajuato, Leon Campus. 20 de Enero No. 929 Col. Obregon, 37320, Leon, Guanajuato, Mexico
| | - Gloria Barbosa-Sabanero
- Medical Sciences Department, Health Sciences Division, University of Guanajuato, Leon Campus. 20 de Enero No. 929 Col. Obregon, 37320, Leon, Guanajuato, Mexico.
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Kuppens RJ, Diène G, Bakker NE, Molinas C, Faye S, Nicolino M, Bernoux D, Delhanty PJD, van der Lely AJ, Allas S, Julien M, Delale T, Tauber M, Hokken-Koelega ACS. Elevated ratio of acylated to unacylated ghrelin in children and young adults with Prader-Willi syndrome. Endocrine 2015; 50:633-42. [PMID: 25989955 PMCID: PMC4662713 DOI: 10.1007/s12020-015-0614-x] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 04/21/2015] [Indexed: 01/13/2023]
Abstract
Prader-Willi syndrome (PWS) is characterized by a switch from failure to thrive to excessive weight gain and hyperphagia in early childhood. Hyperghrelinemia may be involved in the underlying mechanisms of the switch. The purpose of this study is to evaluate acylated ghrelin (AG) and unacylated ghrelin (UAG) levels in PWS and investigate their associations with hyperphagia. This is a cross-sectional clinical study conducted in three PWS expert centers in the Netherlands and France. Levels of AG and UAG and the AG/UAG ratio were determined in 138 patients with PWS (0.2-29.4 years) and compared with 50 age-matched obese subjects (4.3-16.9 years) and 39 healthy controls (0.8-28.6 years). AEBSF was used to inhibit deacylation of AG. As a group, PWS patients had higher AG but similar UAG levels as healthy controls (AG 129.1 vs 82.4 pg/ml, p = 0.016; UAG 135.3 vs 157.3 pg/ml, resp.), resulting in a significantly higher AG/UAG ratio (1.00 vs 0.61, p = 0.001, resp.). Obese subjects had significantly lower AG and UAG levels than PWS and controls (40.3 and 35.3 pg/ml, resp.), but also a high AG/UAG ratio (1.16). The reason for the higher AG/UAG ratio in PWS and obese was, however, completely different, as PWS had a high AG and obese a very low UAG. PWS patients without weight gain or hyperphagia had a similar AG/UAG ratio as age-matched controls, in contrast to those with weight gain and/or hyperphagia who had an elevated AG/UAG ratio. The switch to excessive weight gain in PWS seems to coincide with an increase in the AG/UAG ratio, even prior to the start of hyperphagia.
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Affiliation(s)
- R J Kuppens
- Dutch Growth Research Foundation, Westzeedijk 106, 3016 AH, Rotterdam, The Netherlands.
- Department of Pediatrics, Subdivision of Endocrinology, Erasmus University Medical Center-Sophia Children's Hospital, Rotterdam, The Netherlands.
| | - G Diène
- Unité D'endocrinologie, Obésité, Maladies Osseuses, Génétique et Gynécologie Médicale, Centre de Référence du Syndrome de Prader-Willi, Hôpital des enfants, Toulouse, France
| | - N E Bakker
- Dutch Growth Research Foundation, Westzeedijk 106, 3016 AH, Rotterdam, The Netherlands
- Department of Pediatrics, Subdivision of Endocrinology, Erasmus University Medical Center-Sophia Children's Hospital, Rotterdam, The Netherlands
| | - C Molinas
- Unité D'endocrinologie, Obésité, Maladies Osseuses, Génétique et Gynécologie Médicale, Centre de Référence du Syndrome de Prader-Willi, Hôpital des enfants, Toulouse, France
- Axe pédiatrique du CIC 9302/INSERM. Hôpital des enfants, Toulouse, France
| | - S Faye
- Unité D'endocrinologie, Obésité, Maladies Osseuses, Génétique et Gynécologie Médicale, Centre de Référence du Syndrome de Prader-Willi, Hôpital des enfants, Toulouse, France
| | - M Nicolino
- Division of Pediatric Endocrinology, Hôpital Femme-Mère-Enfant, University of Lyon, Bron/Lyon, France
| | - D Bernoux
- Division of Pediatric Endocrinology, Hôpital Femme-Mère-Enfant, University of Lyon, Bron/Lyon, France
| | - P J D Delhanty
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - A J van der Lely
- Department of Internal Medicine, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - S Allas
- Alizé Pharma, 69130, Ecully, France
| | - M Julien
- Alizé Pharma, 69130, Ecully, France
| | - T Delale
- Alizé Pharma, 69130, Ecully, France
| | - M Tauber
- Unité D'endocrinologie, Obésité, Maladies Osseuses, Génétique et Gynécologie Médicale, Centre de Référence du Syndrome de Prader-Willi, Hôpital des enfants, Toulouse, France
- INSERM U1043, Centre de Physiopathologie de Toulouse Purpan, Université Paul Sabatier, Toulouse, France
| | - A C S Hokken-Koelega
- Dutch Growth Research Foundation, Westzeedijk 106, 3016 AH, Rotterdam, The Netherlands
- Department of Pediatrics, Subdivision of Endocrinology, Erasmus University Medical Center-Sophia Children's Hospital, Rotterdam, The Netherlands
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Unacylated ghrelin restores insulin and autophagic signaling in skeletal muscle of diabetic mice. Pflugers Arch 2015; 467:2555-69. [PMID: 26228926 DOI: 10.1007/s00424-015-1721-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Revised: 06/21/2015] [Accepted: 07/13/2015] [Indexed: 01/04/2023]
Abstract
Impairment of insulin signaling in skeletal muscle detrimentally affects insulin-stimulated disposal of glucose. Restoration of insulin signaling in skeletal muscle is important as muscle is one of the major sites for disposal of blood glucose. Recently, unacylated ghrelin (UnAG) has received attention in diabetic research due to its favorable actions on improving glucose tolerance, glycemic control, and insulin sensitivity. The investigation of UnAG has entered phase Ib clinical trial in type 2 diabetes and phase II clinical trial in hyperphagia in Prader-Willi syndrome. Nonetheless, the precise mechanisms responsible for the anti-diabetic actions of UnAG remain incompletely understood. In this study, we examined the effects of UnAG on restoring the impaired insulin signaling in skeletal muscle of db/db diabetic mice. Our results demonstrated that UnAG effectively restored the impaired insulin signaling in diabetic muscle. UnAG decreased insulin receptor substrate (IRS) phosphorylation, increased protein kinase B (Akt) phosphorylation, and, hence, suppressed mTOR signaling. Consequently, UnAG enhanced Glut4 localization and increased PDH activity in the diabetic skeletal muscle. Intriguingly, our data indicated that UnAG normalized the suppressed autophagic signaling in diabetic muscle. In conclusion, our findings illustrated that UnAG restored the impaired insulin and autophagic signaling in skeletal muscle of diabetic mice, which are valuable to understand the underlying mechanisms of the anti-diabetic action of UnAG at peripheral skeletal muscle level.
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Gaylinn BD, Farhy LS, Nass R, Tong J, Thorner MO. Does des-acyl ghrelin improve glycemic control by decreasing acylated ghrelin levels? Eur J Endocrinol 2015; 173:L1-2. [PMID: 26026595 DOI: 10.1530/eje-14-1131] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Bruce D Gaylinn
- Division of Endocrinology and MetabolismDepartment of MedicineCenter for Diabetes TechnologyUniversity of Virginia, PO Box 801411, Charlottesville, Virginia 22908, USADivision of EndocrinologyDepartment of Medicine, Duke University, Durham, North Carolina 27710, USA
| | - Leon S Farhy
- Division of Endocrinology and MetabolismDepartment of MedicineCenter for Diabetes TechnologyUniversity of Virginia, PO Box 801411, Charlottesville, Virginia 22908, USADivision of EndocrinologyDepartment of Medicine, Duke University, Durham, North Carolina 27710, USA Division of Endocrinology and MetabolismDepartment of MedicineCenter for Diabetes TechnologyUniversity of Virginia, PO Box 801411, Charlottesville, Virginia 22908, USADivision of EndocrinologyDepartment of Medicine, Duke University, Durham, North Carolina 27710, USA
| | - Ralf Nass
- Division of Endocrinology and MetabolismDepartment of MedicineCenter for Diabetes TechnologyUniversity of Virginia, PO Box 801411, Charlottesville, Virginia 22908, USADivision of EndocrinologyDepartment of Medicine, Duke University, Durham, North Carolina 27710, USA
| | - Jenny Tong
- Division of Endocrinology and MetabolismDepartment of MedicineCenter for Diabetes TechnologyUniversity of Virginia, PO Box 801411, Charlottesville, Virginia 22908, USADivision of EndocrinologyDepartment of Medicine, Duke University, Durham, North Carolina 27710, USA
| | - Michael O Thorner
- Division of Endocrinology and MetabolismDepartment of MedicineCenter for Diabetes TechnologyUniversity of Virginia, PO Box 801411, Charlottesville, Virginia 22908, USADivision of EndocrinologyDepartment of Medicine, Duke University, Durham, North Carolina 27710, USA
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Özcan B, Neggers SJCMM, Miller AR, Yang HC, Lucaites V, Abribat T, Allas S, Huisman M, Visser JA, Themmen APN, Sijbrands EJG, Delhanty PJD, van der Lely AJ. Response to inquiry by Gaylinn et al. on 'Administration of UAG improves glycemic control in obese subjects with diabetes'. Eur J Endocrinol 2015; 173:L3-4. [PMID: 26026596 DOI: 10.1530/eje-15-0437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Behiye Özcan
- Department of MedicineErasmus University MC, 3000 CA, Rotterdam, The NetherlandsLilly Research LaboratoriesEli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, USAAlizé Pharma69 130 Ecully, France
| | - Sebastian J C M M Neggers
- Department of MedicineErasmus University MC, 3000 CA, Rotterdam, The NetherlandsLilly Research LaboratoriesEli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, USAAlizé Pharma69 130 Ecully, France
| | - Anne Reifel Miller
- Department of MedicineErasmus University MC, 3000 CA, Rotterdam, The NetherlandsLilly Research LaboratoriesEli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, USAAlizé Pharma69 130 Ecully, France
| | - Hsiu-Chiung Yang
- Department of MedicineErasmus University MC, 3000 CA, Rotterdam, The NetherlandsLilly Research LaboratoriesEli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, USAAlizé Pharma69 130 Ecully, France
| | - Virginia Lucaites
- Department of MedicineErasmus University MC, 3000 CA, Rotterdam, The NetherlandsLilly Research LaboratoriesEli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, USAAlizé Pharma69 130 Ecully, France
| | - Thierry Abribat
- Department of MedicineErasmus University MC, 3000 CA, Rotterdam, The NetherlandsLilly Research LaboratoriesEli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, USAAlizé Pharma69 130 Ecully, France
| | - Soraya Allas
- Department of MedicineErasmus University MC, 3000 CA, Rotterdam, The NetherlandsLilly Research LaboratoriesEli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, USAAlizé Pharma69 130 Ecully, France
| | - Martin Huisman
- Department of MedicineErasmus University MC, 3000 CA, Rotterdam, The NetherlandsLilly Research LaboratoriesEli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, USAAlizé Pharma69 130 Ecully, France
| | - Jenny A Visser
- Department of MedicineErasmus University MC, 3000 CA, Rotterdam, The NetherlandsLilly Research LaboratoriesEli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, USAAlizé Pharma69 130 Ecully, France
| | - Axel P N Themmen
- Department of MedicineErasmus University MC, 3000 CA, Rotterdam, The NetherlandsLilly Research LaboratoriesEli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, USAAlizé Pharma69 130 Ecully, France
| | - Eric J G Sijbrands
- Department of MedicineErasmus University MC, 3000 CA, Rotterdam, The NetherlandsLilly Research LaboratoriesEli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, USAAlizé Pharma69 130 Ecully, France
| | - Patric J D Delhanty
- Department of MedicineErasmus University MC, 3000 CA, Rotterdam, The NetherlandsLilly Research LaboratoriesEli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, USAAlizé Pharma69 130 Ecully, France
| | - Aart Jan van der Lely
- Department of MedicineErasmus University MC, 3000 CA, Rotterdam, The NetherlandsLilly Research LaboratoriesEli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, USAAlizé Pharma69 130 Ecully, France
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Delhanty PJD, Huisman M, Julien M, Mouchain K, Brune P, Themmen APN, Abribat T, van der Lely AJ. The acylated (AG) to unacylated (UAG) ghrelin ratio in esterase inhibitor-treated blood is higher than previously described. Clin Endocrinol (Oxf) 2015; 82:142-6. [PMID: 24810977 DOI: 10.1111/cen.12489] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 04/11/2014] [Accepted: 05/01/2014] [Indexed: 01/13/2023]
Abstract
CONTEXT The acylated/unacylated ghrelin (AG/UAG) ratio has been reported to range from 0·02 to 0·3, suggesting biologically relevant independent regulation of each ghrelin isoform. However, AG is deacylated to UAG by esterases in blood samples, and esterase inhibition is critical for their accurate measurement. Our hypothesis is that at least part of the variation in reported AG and UAG values is due to inconsistent sample preparation. DESIGN A non-interventional study. Quantification with two different, commercially available, ELISA formats of AG and UAG in venous plasma stabilized or not with 4-(2-aminoethyl) benzenesulphonyl fluoride (AEBSF) and stored for 0-6 months at -20 or -80 °C. PARTICIPANTS Healthy, non-obese, adults (n = 8; 4 women), age 26-42 yrs, after an overnight fast. MEASUREMENTS AG and UAG stability following different methods of sample treatment and storage. RESULTS Non-AEBSF plasma contained low AG and high UAG (>270 pg/ml) indicating rapid conversion of AG to UAG. However, AEBSF plasma, stored at -80 °C and measured at 0, 1, 3 and 6 months contained AG and UAG ranges of 12-350 and 17-170 pg/ml, respectively. Mean (SEM) AG/UAG ratios were 1·7(0·3), 1·2(0·2), 1·5(0·3) and 1·8(0·5) at each time point with no significant effect of storage period. CONCLUSIONS AG and UAG levels measured in AEBSF-stabilized plasma indicate that the AG/UAG ratio is markedly higher than previously described and that UAG is a physiological component of the circulation. This highlights the importance of immediately stabilizing blood samples on collection for determination of both AG and UAG concentrations and provides a valuable tool for their measurement in physiological and interventional studies.
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Zabarovskaja S, Freda P, Williams JJ, Kunavarapu C, Lamanca J, Mancini D, Lund LH. Acylation of ghrelin is increased in heart failure and decreases post heart transplantation. SCAND CARDIOVASC J 2014; 48:343-8. [PMID: 25130063 DOI: 10.3109/14017431.2014.955052] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVES Ghrelin is an anabolic hormone that is elevated in heart failure (HF), with resistance to its anabolic effects. This resolves after heart transplantation (HTx). Ghrelin exists in acylated and des-acyl forms, with the acylated form being primarily responsible for endocrine actions. We tested the hypothesis that ghrelin derangements in HF are due to inadequate acylation and that this resolves post transplantation. DESIGN Plasma levels of des-acyl and acylated ghrelin and acylated/total ratios were assessed in HF (n = 20), post-HTx (n = 35), and healthy controls (n = 4), and correlated with each other and with clinical parameters. RESULTS Median (interquartile range) of des-acyl ghrelin level, was 167 (121-195) pg/ml in HF versus 149 (130-223) pg/ml in post-HTx, p = NS. Acylated ghrelin level was 76 (51-99) pg/ml versus 13 (0-30) pg/ml, p < 0.001. Acylated/total ratios were 0.33 (0.20-0.47) versus 0.08 (0-0.13), p < 0.001. The correlation between acylated and total ghrelin levels was greater in HF than that in HTx. Acyl ghrelin correlated inversely with body mass index in HF, but not in HTx. CONCLUSION Acylated ghrelin and the acylated/total ratio were dramatically higher in HF compared with those in HTx. Acylation rather than secretion of ghrelin is upregulated in HF and the resistance to ghrelin's anabolic and appetite-stimulating effects is not at the level of acylation, but downstream at the ghrelin-receptor level.
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Cameron KO, Bhattacharya SK, Loomis AK. Small Molecule Ghrelin Receptor Inverse Agonists and Antagonists. J Med Chem 2014; 57:8671-91. [DOI: 10.1021/jm5003183] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Kimberly O. Cameron
- Worldwide
Medicinal Chemistry, Pfizer Worldwide Research and Development, 610
Main Street, Cambridge, Massachusetts 02139, United States
| | - Samit K. Bhattacharya
- Worldwide
Medicinal Chemistry, Pfizer Worldwide Research and Development, 610
Main Street, Cambridge, Massachusetts 02139, United States
| | - A. Katrina Loomis
- Pharmatherapeutics
Precision Medicine, Pfizer Worldwide Research and Development, Eastern
Point Road, Groton, Connecticut 06340, United States
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Heppner KM, Tong J. Mechanisms in endocrinology: regulation of glucose metabolism by the ghrelin system: multiple players and multiple actions. Eur J Endocrinol 2014; 171:R21-32. [PMID: 24714083 DOI: 10.1530/eje-14-0183] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Ghrelin is a 28-amino acid peptide secreted mainly from the X/A-like cells of the stomach. Ghrelin is found in circulation in both des-acyl (dAG) and acyl forms (AG). Acylation is catalyzed by the enzyme ghrelin O-acyltransferase (GOAT). AG acts on the GH secretagogue receptor (GHSR) in the CNS to promote feeding and adiposity and also acts on GHSR in the pancreas to inhibit glucose-stimulated insulin secretion. These well-described actions of AG have made it a popular target for obesity and type 2 diabetes mellitus pharmacotherapies. However, despite the lack of a cognate receptor, dAG appears to have gluco-regulatory action, which adds an additional layer of complexity to ghrelin's regulation of glucose metabolism. This review discusses the current literature on the gluco-regulatory action of the ghrelin system (dAG, AG, GHSR, and GOAT) with specific emphasis aimed toward distinguishing AG vs dAG action.
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Affiliation(s)
- Kristy M Heppner
- Division of DiabetesObesity and Metabolism, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, USA andDivision of EndocrinologyDiabetes and Metabolism, Department of Medicine, University of Cincinnati, 260 Stetson Street, Suite 4200, Cincinnati, Ohio 45219-0547, USA
| | - Jenny Tong
- Division of DiabetesObesity and Metabolism, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, USA andDivision of EndocrinologyDiabetes and Metabolism, Department of Medicine, University of Cincinnati, 260 Stetson Street, Suite 4200, Cincinnati, Ohio 45219-0547, USA
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44
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Tong J, Davis HW, Summer S, Benoit SC, Haque A, Bidlingmaier M, Tschöp MH, D'Alessio D. Acute administration of unacylated ghrelin has no effect on Basal or stimulated insulin secretion in healthy humans. Diabetes 2014; 63:2309-19. [PMID: 24550190 PMCID: PMC4066344 DOI: 10.2337/db13-1598] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Unacylated ghrelin (UAG) is the predominant ghrelin isoform in the circulation. Despite its inability to activate the classical ghrelin receptor, preclinical studies suggest that UAG may promote β-cell function. We hypothesized that UAG would oppose the effects of acylated ghrelin (AG) on insulin secretion and glucose tolerance. AG (1 µg/kg/h), UAG (4 µg/kg/h), combined AG+UAG, or saline were infused to 17 healthy subjects (9 men and 8 women) on four occasions in randomized order. Ghrelin was infused for 30 min to achieve steady-state levels and continued through a 3-h intravenous glucose tolerance test. The acute insulin response to glucose (AIRg), insulin sensitivity index (SI), disposition index (DI), and intravenous glucose tolerance (kg) were compared for each subject during the four infusions. AG infusion raised fasting glucose levels but had no effect on fasting plasma insulin. Compared with the saline control, AG and AG+UAG both decreased AIRg, but UAG alone had no effect. SI did not differ among the treatments. AG, but not UAG, reduced DI and kg and increased plasma growth hormone. UAG did not alter growth hormone, cortisol, glucagon, or free fatty acid levels. UAG selectively decreased glucose and fructose consumption compared with the other treatments. In contrast to previous reports, acute administration of UAG does not have independent effects on glucose tolerance or β-cell function and neither augments nor antagonizes the effects of AG.
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Affiliation(s)
- Jenny Tong
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Cincinnati, Cincinnati, OH
| | - Harold W Davis
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Cincinnati, Cincinnati, OH
| | - Suzanne Summer
- Clinical Translational Research Center, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Stephen C Benoit
- Department of Psychiatry, University of Cincinnati, Cincinnati, OH
| | - Ahrar Haque
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Cincinnati, Cincinnati, OH
| | - Martin Bidlingmaier
- Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität, Munich, Germany
| | - Matthias H Tschöp
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Cincinnati, Cincinnati, OHInstitute for Obesity and Diabetes, Helmholtz Center Munich and Division of Metabolic Diseases, Department of Medicine, Technical University, Munich, Germany
| | - David D'Alessio
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Cincinnati, Cincinnati, OHCincinnati Veterans Affairs Medical Center, Cincinnati, OH
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Reversing Metabolic Diseases Through Diabetes Surgery: Do the Proximal Gut and Related Hormones Play Key Roles in Glucose Homeostasis? Arch Med Res 2013; 44:407-8. [DOI: 10.1016/j.arcmed.2013.09.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Accepted: 08/22/2013] [Indexed: 01/19/2023]
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