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Exogenous Ghrelin Increases Plasma Insulin Level in Diabetic Rats
Haba Elabadlah1,2, Rasheed Hameed3, Crystal D'Souza3
1Department of Pharmacology, College of Medicine & Health Sciences, United Arab Emirates University, P.O.B. 17666, Al Ain, United Arab Emirates.
Biomolecules
|April 25, 2020
Summary
Ghrelin enhances insulin production and secretion by pancreatic beta cells, improving glucose homeostasis in both normal and diabetic rats. This peptide co-localizes with insulin, suggesting a direct role in regulating insulin levels.
Area of Science:
- Endocrinology
- Metabolic Research
- Diabetes Mellitus Research
Background:
- Ghrelin, a peptide hormone, regulates appetite and growth hormone secretion.
- Its role in insulin secretion and glucose homeostasis is debated, with conflicting literature.
- Understanding ghrelin's function in pancreatic islets is crucial for diabetes research.
Purpose of the Study:
- To investigate the impact of chronic ghrelin treatment on glucose, body weight, and insulin levels in normal and diabetic rats.
- To examine ghrelin's distribution and co-localization with insulin in pancreatic islet cells.
- To assess ghrelin's ability to stimulate insulin release from a beta cell line.
Main Methods:
- Daily intraperitoneal injections of ghrelin (5 µg/kg) or saline for four weeks in male Wistar rats.
- Induction of diabetes using streptozotocin in specific rat groups.
- Immunohistochemistry, immune-electron microscopy, and in vitro beta cell assays (CRL11065).
Main Results:
- Ghrelin administration increased beta cell count and serum insulin levels in both normal and diabetic rats.
- Ghrelin was found to co-localize with insulin in pancreatic islet cells, with altered distribution in diabetes.
- Ghrelin significantly stimulated insulin release from the CRL11065 beta cell line at specific concentrations (10-6M and 10-12M).
Conclusions:
- Ghrelin co-localizes with insulin within the secretory granules of pancreatic beta cells.
- Chronic ghrelin treatment enhances insulin production and secretion, positively impacting glucose metabolism.
- Ghrelin shows therapeutic potential for managing type 2 diabetes mellitus by improving insulin regulation.
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