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Abstract
Esophageal cancer has traditionally been a disease with poor long term outcomes in terms of both survival and quality of life. In combination with surgical and pharmacologic therapy, nutrition support has been demonstrated to improve patient tolerance of treatment, quality of life, and longterm outcomes. An aggressive multi-disciplinary approach is warranted with nutrition support remaining a cornerstone in management. Historically, nutrition support has focused on adequate caloric provision to prevent weight loss and allow for tolerance of treatment regimens. Alterations in metabolism occur in these patients making their use of available calories inefficient and the future of nutritional support may lie in the ability to alter this deranged metabolism. The purpose of this article is to review the current literature surrounding the etiology, treatment, and role of nutrition support in improving outcomes in esophageal cancer.
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Garcia JM, Friend J, Allen S. Therapeutic potential of anamorelin, a novel, oral ghrelin mimetic, in patients with cancer-related cachexia: a multicenter, randomized, double-blind, crossover, pilot study. Support Care Cancer 2012; 21:129-37. [PMID: 22699302 DOI: 10.1007/s00520-012-1500-1] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Accepted: 05/14/2012] [Indexed: 12/28/2022]
Abstract
PURPOSE Cachexia in cancer adversely affects patients' perception of symptoms, well-being, and response to therapy, and shortens survival. Anamorelin, an oral mimetic of ghrelin, has been shown to increase body weight and anabolic hormone levels in healthy volunteers and is being investigated to treat cancer cachexia. METHODS This multicenter, double-blind, placebo-controlled, crossover study evaluated the effects of anamorelin in 16 patients with different cancers and cachexia. Patients were randomly assigned to anamorelin 50 mg/day or placebo for 3 days. A 3- to 7-day washout period followed and then treatments were switched. Assessments included body weight, appetite, food intake, growth hormone (GH) levels, patient-reported symptom assessments (e.g., the Anderson Symptom Assessment Scale [ASAS] and also an inclusion criterion), and safety. RESULTS Anamorelin significantly increased body weight compared with placebo (0.77 kg vs. -0.33 kg). Food intake increased compared with placebo, but not significantly. GH significantly increased at all time points (0.5-4 h postdose). Insulin-like growth factor-1 (IGF-1) significantly increased by 54.09 ng/mL with anamorelin treatment compared with -3.56 ng/mL for placebo; significant changes in insulin-like growth factor-binding protein 3 (IGFBP-3) were 0.75 μg/mL vs. -0.19 μg/mL, respectively. Patient-reported symptoms, including appetite as measured by ASAS, significantly improved with anamorelin (8.1 vs. 1.0 for placebo). Adverse events (AEs) in four patients were possibly or probably related to anamorelin: hyperglycemia (two patients), nausea (one patient), and dizziness (one patient). Most AEs were mild; no patients withdrew due to AEs. CONCLUSIONS Anamorelin showed significant metabolic, clinical, and patient-rated effects in cancer cachexia. Further studies are warranted.
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Affiliation(s)
- José M Garcia
- Division of Endocrinology, Diabetes and Metabolism, Baylor College of Medicine, Houston, TX, USA.
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53
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Hoveyda HR, Marsault E, Gagnon R, Mathieu AP, Vézina M, Landry A, Wang Z, Benakli K, Beaubien S, Saint-Louis C, Brassard M, Pinault JF, Ouellet L, Bhat S, Ramaseshan M, Peng X, Foucher L, Beauchemin S, Bhérer P, Veber DF, Peterson ML, Fraser GL. Optimization of the Potency and Pharmacokinetic Properties of a Macrocyclic Ghrelin Receptor Agonist (Part I): Development of Ulimorelin (TZP-101) from Hit to Clinic. J Med Chem 2011; 54:8305-20. [DOI: 10.1021/jm2007062] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Hamid R. Hoveyda
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Eric Marsault
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - René Gagnon
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Axel P. Mathieu
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Martin Vézina
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Annick Landry
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Zhigang Wang
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Kamel Benakli
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Sylvie Beaubien
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Carl Saint-Louis
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Martin Brassard
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | | | - Luc Ouellet
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Shridhar Bhat
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Mahesh Ramaseshan
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Xiaowen Peng
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Laurence Foucher
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Sophie Beauchemin
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Patrick Bhérer
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Daniel F. Veber
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Mark L. Peterson
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
| | - Graeme L. Fraser
- Tranzyme Pharma Inc., 3001,
12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada
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54
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Abstract
Many respiratory diseases besides lung cancer are still not curable. There is an unmet need for palliative care, especially in non-malignant conditions. In this article we focus on symptomatic treatment of typical symptoms in respiratory disease beyond causal treatment.
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Affiliation(s)
- D F Heigener
- Zentrum für Pneumologie und Thoraxchirurgie, Krankenhaus Grosshansdorf, Grosshansdorf, Germany
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55
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Akamizu T, Kangawa K. Therapeutic applications of ghrelin to cachexia utilizing its appetite-stimulating effect. Peptides 2011; 32:2295-300. [PMID: 21635929 DOI: 10.1016/j.peptides.2011.05.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Revised: 05/13/2011] [Accepted: 05/16/2011] [Indexed: 02/07/2023]
Abstract
Ghrelin, which is a natural ligand for the growth hormone (GH)-secretagogue receptor (GHS-R), stimulates food intake in both animals and humans. Ghrelin is the only circulating hormone known to stimulate appetite in humans. Ghrelin also stimulates GH secretion and inhibits the production of anorectic proinflammatory cytokines. As GH is an anabolic hormone, protein stores are spared at the expense of fat during conditions of caloric restriction. Thus, ghrelin exhibits anti-cachectic actions via both GH-dependent and -independent mechanisms. Several studies are evaluating the efficacy of ghrelin in the treatment of cachexia caused by a variety of diseases, including congestive heart failure, chronic obstructive pulmonary disease, cancer, and end-stage renal disease. These studies will hopefully lead to the development of novel therapeutic applications for ghrelin in the future. This review summarizes the recent advances in this area of research.
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Affiliation(s)
- Takashi Akamizu
- The First Department of Medicine, Wakayama Medical University, Wakayama 641-8509, Japan.
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56
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A review of weight control strategies and their effects on the regulation of hormonal balance. J Nutr Metab 2011; 2011:237932. [PMID: 21822485 PMCID: PMC3147122 DOI: 10.1155/2011/237932] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Accepted: 05/20/2011] [Indexed: 01/11/2023] Open
Abstract
The estimated prevalence of obesity in the USA is 72.5 million adults with costs attributed to obesity more than 147 billion dollars per year. Though caloric restriction has been used extensively in weight control studies, short-term success has been difficult to achieve, with long-term success of weight control being even more elusive. Therefore, novel approaches are needed to control the rates of obesity that are occurring globally. The purpose of this paper is to provide a synopsis of how exercise, sleep, psychological stress, and meal frequency and composition affect levels of ghrelin, cortisol, insulin GLP-1, and leptin and weight control. We will provide information regarding how hormones respond to various lifestyle factors which may affect appetite control, hunger, satiety, and weight control.
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57
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DeBoer MD. Ghrelin and cachexia: will treatment with GHSR-1a agonists make a difference for patients suffering from chronic wasting syndromes? Mol Cell Endocrinol 2011; 340:97-105. [PMID: 21354462 PMCID: PMC3114250 DOI: 10.1016/j.mce.2011.02.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Revised: 02/15/2011] [Accepted: 02/15/2011] [Indexed: 01/24/2023]
Abstract
Cachexia is a syndrome of wasting and anorexia that worsens the prognosis of many chronic diseases including cancer, chronic kidney disease, chronic heart disease and chronic obstructive pulmonary disease. Properties of the orexigenic hormone ghrelin-including appetite-stimulation, weight-gain production and increased cardiac output make it a logical treatment for cachexia. While endogenous ghrelin levels are increased in the setting of cachexia, treatment with ghrelin and other GHSR-1a agonists in animal models of cachexia and in humans with cachexia has demonstrated consistent effects of increased appetite and improved weight gain. These positive effects occur in multiple underlying diseases associated with cachexia and appear to be sustained over treatment duration of up to 12 weeks. The mechanism of action in producing these effects is likely related to stimulation of central appetite centers such as the central melanocortin system and to increased growth hormone release, though ghrelin's effects may also relate to decreased systemic inflammation and other direct and indirect actions. Questions regarding the long-term safety of ghrelin treatment are still unanswered, as is the important question of whether successful treatment of cachexia will improve the prognosis of the underlying disease itself.
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Affiliation(s)
- Mark D DeBoer
- Department of Pediatrics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA.
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58
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Dodson S, Baracos VE, Jatoi A, Evans WJ, Cella D, Dalton JT, Steiner MS. Muscle wasting in cancer cachexia: clinical implications, diagnosis, and emerging treatment strategies. Annu Rev Med 2011; 62:265-79. [PMID: 20731602 DOI: 10.1146/annurev-med-061509-131248] [Citation(s) in RCA: 233] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Cancer cachexia is a complex metabolic condition characterized by loss of skeletal muscle. Common clinical manifestations include muscle wasting, anemia, reduced caloric intake, and altered immune function, which contribute to increased disability, fatigue, diminished quality of life, and reduced survival. The prevalence of cachexia and the impact of this disorder on the patient and family underscore the need for effective management strategies. Dietary supplementation and appetite stimulation alone are inadequate to reverse the underlying metabolic abnormalities of cancer cachexia and have limited long-term impact on patient quality of life and survival. Therapies that can increase muscle mass and physical performance may be a promising option; however, there are currently no drugs approved for the prevention or treatment of cancer cachexia. Several agents are in clinical development, including anabolic agents, such as selective androgen receptor modulators and drugs targeting inflammatory cytokines that promote skeletal muscle catabolism.
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59
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Abstract
PURPOSE OF REVIEW Cachexia affects millions of cancer patients around the world. Though its causes are poorly understood, its devastating impact on the patient and their loved ones underscore the urgency of this unmet medical need. Recent research efforts suggest multiple body systems are dysregulated in cachexia, not only increasing the challenge in effectively treating the disease but also expanding the opportunities for intervention. RECENT FINDINGS Agents as diverse as anti-inflammatory monoclonal antibodies and novel anabolic small molecules are under clinical evaluation for their ability to prevent and treat wasting. The therapies evaluated to date range in their ability to improve appetite, mitigate weight loss and reverse undesirable changes in body composition and physical function. SUMMARY An increased understanding of cancer cachexia, both mechanistically and its impact on cancer patients' struggle with their disease, has resulted in diverse therapeutic concepts. Recent clinical efforts demonstrate progress with novel therapies but fall short of effectively treating most cachectic patients and highlight a clear need for further research. Given the inherent heterogeneity of cancer patients and the significant impact of muscle wasting on morbidity and mortality, continued research efforts are critical in developing effective therapies to prevent and treat cancer cachexia.
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60
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Morozumi N, Hanada T, Habara H, Yamaki A, Furuya M, Nakatsuka T, Inomata N, Minamitake Y, Ohsuye K, Kangawa K. The role of C-terminal part of ghrelin in pharmacokinetic profile and biological activity in rats. Peptides 2011; 32:1001-7. [PMID: 21291937 DOI: 10.1016/j.peptides.2011.01.021] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Revised: 01/22/2011] [Accepted: 01/24/2011] [Indexed: 10/18/2022]
Abstract
Ghrelin is an endogenous ligand for growth hormone secretagogue receptor 1a (GHS-R1a), and consists of 28 amino acid residues with octanoyl modification at Ser(3). The previous studies have revealed that N-terminal part of ghrelin including modified Ser(3) is the active core for the activation of GHS-R1a. On the other hand, the role of C-terminal (8-28) region in ghrelin has not been clarified yet. In the present study, we prepared human ghrelin, C-terminal truncated ghrelin derivatives and anamorelin, a small molecular GHS compound which supposedly mimics the N-terminal active core, and examined GHS-R1a agonist activity in vitro, pharmacokinetic (PK) profile and growth hormone (GH) releasing activity in rats. All compounds demonstrated potent GHS-R1a agonist activities in vitro. Although the lack of C-terminal two amino acids did not modify PK profile and GH releasing activity, the deletion of C-terminal 8 and 20 amino acids affected them, and ghrelin(1-7)-Lys-NH(2) exhibited very short plasma half-life and low GH releasing activity in vivo. In rat plasma, ghrelin(1-7)-Lys-NH(2) was degraded more rapidly than ghrelin, suggesting that C-terminal part of ghrelin protected octanoylation of Ser(3) from plasma esterases. Subdiaphragmatic vagotomy significantly attenuated GH response to ghrelin but not to anamorelin. These results suggest that the C-terminal part of ghrelin has an important role in the biological activity in vivo. We also found that ghrelin stimulated GH release mainly via a vagal nerve pathway but anamorelin augmented GH release possibly by directly acting on brain in rats.
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Affiliation(s)
- Naomi Morozumi
- Faculty of Pharmacology I, Asubio Pharma Co, Ltd, 6-4-3 Minatojima-Minamimachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan
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61
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Abstract
Ghrelin, a natural ligand for the growth hormone (GH)-secretagogue receptor, is primarily produced in the stomach. Administration of ghrelin stimulates food intake and GH secretion in both animals and humans. Ghrelin is the only circulating hormone known to stimulate appetite in humans. As GH is an anabolic hormone, protein stores are spared at the expense of fat during conditions of caloric restriction. Ghrelin also inhibits the production of anorectic proinflammatory cytokines. Thus, ghrelin exhibits anti-cachectic actions via both GH-dependent and -independent mechanisms. Several studies are evaluating the efficacy of ghrelin in the treatment of cachexia caused by a variety of diseases, including congestive heart failure, chronic obstructive pulmonary disease, cancer, and end-stage renal disease. These studies will hopefully lead to the development of novel clinical applications for ghrelin in the future. These studies have also facilitated a better understanding of the molecular basis of the anti-catabolic effects of ghrelin. This review summarizes the recent advances in this area of research.
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62
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De Vriese C, Perret J, Delporte C. Focus on the short- and long-term effects of ghrelin on energy homeostasis. Nutrition 2010; 26:579-84. [DOI: 10.1016/j.nut.2009.09.013] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2009] [Accepted: 09/17/2009] [Indexed: 02/06/2023]
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63
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Ferens DM, Yin L, Ohashi-Doi K, Habgood M, Bron R, Brock JA, Gale JD, Furness JB. Evidence for functional ghrelin receptors on parasympathetic preganglionic neurons of micturition control pathways in the rat. Clin Exp Pharmacol Physiol 2010; 37:926-32. [DOI: 10.1111/j.1440-1681.2010.05409.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Gullett NP, Hebbar G, Ziegler TR. Update on clinical trials of growth factors and anabolic steroids in cachexia and wasting. Am J Clin Nutr 2010; 91:1143S-1147S. [PMID: 20164318 PMCID: PMC2844687 DOI: 10.3945/ajcn.2010.28608e] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
This article and others that focused on the clinical features, mechanisms, and epidemiology of skeletal muscle loss and wasting in chronic diseases, which include chronic kidney disease, cancer, and AIDS, were presented at a symposium entitled "Cachexia and Wasting: Recent Breakthroughs in Understanding and Opportunities for Intervention," held at Experimental Biology 2009. The clinical and anabolic efficacy of specific growth factors and anabolic steroids (eg, growth hormone, testosterone, megestrol acetate) in malnutrition and other catabolic states has been the subject of considerable research during the past several decades. Research on the effects of these agents in cachexia or wasting conditions, characterized by progressive loss of skeletal muscle and adipose tissue, focused on patients with AIDS in the early 1990s, when the devastating effects of the loss of body weight, lean body mass, and adipose tissue were recognized as contributors to these patients' mortality. These same agents have also been studied as methods to attenuate the catabolic responses observed in cancer-induced cachexia and in wasting induced by chronic obstructive pulmonary disease, congestive heart failure, renal failure, and other conditions. This article provides an updated review of recent clinical trials that specifically examined the potential therapeutic roles of growth hormone, testosterone, oxandrolone, and megestrol acetate and emerging data on the orexigenic peptide ghrelin, in human cachexia and wasting.
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Affiliation(s)
- Norleena P Gullett
- Department of Radiation Oncology, Emory University School of Medicine, Atlanta, GA, USA
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Veldhuis JD, Bowers CY. Integrating GHS into the Ghrelin System. INTERNATIONAL JOURNAL OF PEPTIDES 2010; 2010:879503. [PMID: 20798846 PMCID: PMC2925380 DOI: 10.1155/2010/879503] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/24/2009] [Accepted: 12/30/2009] [Indexed: 12/21/2022]
Abstract
Oligopeptide derivatives of metenkephalin were found to stimulate growth-hormone (GH) release directly by pituitary somatotrope cells in vitro in 1977. Members of this class of peptides and nonpeptidyl mimetics are referred to as GH secretagogues (GHSs). A specific guanosine triphosphatate-binding protein-associated heptahelical transmembrane receptor for GHS was cloned in 1996. An endogenous ligand for the GHS receptor, acylghrelin, was identified in 1999. Expression of ghrelin and homonymous receptor occurs in the brain, pituitary gland, stomach, endothelium/vascular smooth muscle, pancreas, placenta, intestine, heart, bone, and other tissues. Principal actions of this peptidergic system include stimulation of GH release via combined hypothalamopituitary mechanisms, orexigenesis (appetitive enhancement), insulinostasis (inhibition of insulin secretion), cardiovascular effects (decreased mean arterial pressure and vasodilation), stimulation of gastric motility and acid secretion, adipogenesis with repression of fat oxidation, and antiapoptosis (antagonism of endothelial, neuronal, and cardiomyocyte death). The array of known and proposed interactions of ghrelin with key metabolic signals makes ghrelin and its receptor prime targets for drug development.
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Affiliation(s)
- Johannes D. Veldhuis
- Department of Medicine, Endocrine Research Unit, Mayo School of Graduate Medical Education, Clinical Translational Science Center, Mayo Clinic, Rochester, MN 55905, USA
| | - Cyril Y. Bowers
- Division of Endocrinology, Department of Internal Medicine, Tulane University Health Sciences Center, New Orleans, LA 70112, USA
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Castañeda TR, Tong J, Datta R, Culler M, Tschöp MH. Ghrelin in the regulation of body weight and metabolism. Front Neuroendocrinol 2010; 31:44-60. [PMID: 19896496 DOI: 10.1016/j.yfrne.2009.10.008] [Citation(s) in RCA: 241] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2009] [Revised: 10/26/2009] [Accepted: 10/26/2009] [Indexed: 12/25/2022]
Abstract
Ghrelin, a peptide hormone predominantly produced by the stomach, was isolated as the endogenous ligand for the growth hormone secretagogue receptor. Ghrelin is a potent stimulator of growth hormone (GH) secretion and is the only circulatory hormone known to potently enhance feeding and weight gain and to regulate energy homeostasis following central and systemic administration. Therapeutic intervention with ghrelin in catabolic situations may induce a combination of enhanced food intake, increased gastric emptying and nutrient storage, coupled with an increase in GH thereby linking nutrient partitioning with growth and repair processes. These qualities have fostered the idea that ghrelin-based compounds may have therapeutic utility in treating malnutrition and wasting induced by various sub-acute and chronic disorders. Conversely, compounds that inhibit ghrelin action may be useful for the prevention or treatment of metabolic syndrome components such as obesity, impaired lipid metabolism or insulin resistance. In recent years, the effects of ghrelin on glucose homeostasis, memory function and gastrointestinal motility have attracted considerable amount of attention and revealed novel therapeutic targets in treating a wide range of pathologic conditions. Furthermore, discovery of ghrelin O-acyltransferase has also opened new research opportunities that could lead to major understanding of ghrelin physiology. This review summarizes the current knowledge on ghrelin synthesis, secretion, mechanism of action and biological functions with an additional focus on potential for ghrelin-based pharmacotherapies.
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Affiliation(s)
- T R Castañeda
- Dept. of Physiology and Pharmacology, Center for Diabetes and Endocrine Research, College of Medicine, University of Toledo, Toledo, OH, USA
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