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Drug Insight: the functions of ghrelin and its potential as a multitherapeutic hormone

Abstract

The endogenous ligand for the growth-hormone (GH) secretagogue receptor was purified from stomach and named ghrelin. It has potent GH-releasing activity and stimulates appetite by acting on the hypothalamic arcuate nucleus, a region known to control food intake. Ghrelin thus plays important roles in maintaining GH release and energy homeostasis in vertebrates. Ghrelin, moreover, stimulates gastric motility and acid secretion, shows positive cardiovascular effects, and has direct actions on bone formation. The diverse functions of ghrelin raise the possibility of its clinical application for GH deficiency, eating disorders, gastrointestinal disease, cardiovascular disease, osteoporosis and aging.

Key Points

  • Ghrelin is a hormone secreted mainly from the stomach into the circulation

  • Ghrelin stimulates growth-hormone release

  • Ghrelin stimulates appetite and increases food intake

  • Ghrelin is useful for treatment of weight loss and eating disorders

  • Gastric bypass decreases ghrelin levels and leads to weight loss

  • Ghrelin improves cardiovascular function

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Figure 1: From the ghrelin precursor to an active peptide
Figure 2: Regulation of growth-hormone release from the pituitary by ghrelin
Figure 3: Hypothalamic appetite regulation by ghrelin and leptin

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Acknowledgements

The authors' studies are supported by grants from the Promotion of Basic Research Activities for Innovative Biosciences (PROBRAIN), the Ministry of Education, Culture, Sports, Science, and Technology of Japan, and the Program for Promotion of Fundamental Studies in Health Sciences of the National Institute of Biomedical Innovation (NIBIO) of Japan. We express our gratitude to students, collaborators, and fellow scientists who shared their scientific interests with us and obtained the findings we have reviewed in this article.

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Correspondence to Masayasu Kojima.

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Kojima, M., Kangawa, K. Drug Insight: the functions of ghrelin and its potential as a multitherapeutic hormone. Nat Rev Endocrinol 2, 80–88 (2006). https://doi.org/10.1038/ncpendmet0080

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  • DOI: https://doi.org/10.1038/ncpendmet0080

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