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Coculture Analysis of Extracellular Protein Interactions Affecting Insulin Secretion by Pancreatic Beta Cells
Published on: June 15, 2013
Homocysteine and other structurally-diverse amino thiols can alter pancreatic beta cell function without evoking
Steven Patterson1, Peter R Flatt, Neville H McClenaghan
1School of Biomedical Sciences, University of Ulster, Coleraine BT52 1SA, UK. s.patterson@ulster.ac.uk
Biochimica Et Biophysica Acta
|April 25, 2006
Summary
Certain amino thiols, including homocysteine, impair pancreatic beta cell function and insulin secretion. These neurotoxins negatively affect insulin release without compromising cell viability, highlighting potential risks to metabolic health.
Area of Science:
- Biochemistry
- Endocrinology
- Cell Biology
Background:
- Homocysteine and related amino thiols are recognized neurotoxins.
- Homocysteine thiolactone exhibits cytotoxicity to various cell types.
- Pancreatic beta cells share phenotypic similarities with neuronal cells.
Purpose of the Study:
- To investigate the detrimental effects of amino thiols on pancreatic beta cell function.
- To assess the impact of homocysteine and related compounds on insulin secretion.
- To utilize clonal pancreatic BRIN-BD11 cells as a model system.
Main Methods:
- Exposure of BRIN-BD11 cells to various concentrations of amino thiols.
- Measurement of insulin secretion under basal and stimulatory glucose conditions.
- Assessment of insulin secretion in response to secretagogues like alanine, Ca(2+), forskolin, PMA, GLP-1, and KCl.
Main Results:
- Homocysteine, homocysteine thiolactone, and homocysteine sulphinic acid inhibited insulin secretion concentration-dependently.
- Cysteic acid also inhibited insulin secretion at stimulatory glucose levels.
- While cell viability was unaffected, responses to alanine, Ca(2+), forskolin, PMA, GLP-1, and KCl were impaired by specific amino thiols.
Conclusions:
- Homocysteine, homocysteine thiolactone, and other amino thiols can cause dysfunctional insulin secretion in pancreatic beta cells.
- These findings suggest a potential mechanism linking amino thiol toxicity to impaired glucose homeostasis.
- Further research is warranted to explore the clinical implications of these effects.
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