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Ghrelin function in insulin release and glucose metabolism
1Division of Integrative Physiology, Department of Physiology, Jichi Medical University School of Medicine, Shimotsuke, Tochigi 329-0498, Japan. dezaki@jichi.ac.jp
Endocrine Development
|May 9, 2013
Summary
Ghrelin, a hormone primarily from the stomach, inhibits insulin release. Blocking this ghrelin-receptor system in pancreatic islets enhances insulin secretion, offering a new strategy for type 2 diabetes treatment.
Area of Science:
- Endocrinology
- Metabolic Research
- Neuroendocrinology
Background:
- Ghrelin, a peptide hormone, influences growth hormone release, feeding, and cardiovascular functions.
- Ghrelin and its receptor (GHS-R) are present in pancreatic islets, where ghrelin inhibits insulin release.
- Ghrelin O-acyltransferase (GOAT) is crucial for ghrelin's activity and is also found in islets.
Purpose of the Study:
- To investigate the role of the ghrelin-GHS-R system in pancreatic islets regarding insulin secretion.
- To explore the potential of targeting this system for treating type 2 diabetes.
Main Methods:
- Studied ghrelin, GHS-R, and GOAT expression and function in pancreatic islets.
- Utilized pharmacological and genetic blockade of the ghrelin system in vitro and in vivo models.
- Assessed effects on glucose-induced insulin release and glucose tolerance in obese models.
Main Results:
- Ghrelin inhibits insulin release from pancreatic islets through unique signaling pathways.
- Blocking islet-derived ghrelin or its receptor significantly increases glucose-stimulated insulin secretion.
- Ablation of ghrelin, GHS-R, or GOAT improves insulin release and glucose tolerance in obese models.
Conclusions:
- The ghrelin-GHS-R system in pancreatic islets plays a key role in regulating insulin secretion.
- Targeting the ghrelin-GHS-R system, particularly its islet component, offers a promising therapeutic strategy for type 2 diabetes.
- Ghrelin antagonism presents a novel approach to manage dysregulated insulin release in diabetes.
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