Pancreatic beta cell replication induced by glucocorticoids in subhuman primates

Area of Science:

• Endocrinology
• Cell Biology
• Primate Research

Background:

• Adrenal glucocorticoids are known to affect glucose metabolism.
• The impact of glucocorticoids on pancreatic islet cell dynamics requires further elucidation.

Purpose of the Study:

• To investigate the effects of exogenous glucocorticoids on pancreatic islet morphology and function in Macaca cyclopis.
• To assess beta cell proliferation and insulin secretion in response to glucocorticoid administration.

Main Methods:

• Light microscopy, autoradiography, and electron microscopy were employed.
• Monkeys received glucocorticoid injections, and tissues were analyzed.
• (3)H-thymidine was used to label proliferating cells.

Main Results:

• Glucocorticoid treatment induced mild hyperglycemia and elevated serum insulin.
• Pancreatic beta cells showed degranulation and hyperplasia, with increased mitotic activity.
• These changes correlated with serum insulin levels and were reversible upon treatment cessation.

Conclusions:

• Glucocorticoids stimulate pancreatic beta cell proliferation and insulin production in primates.
• Newly formed beta cells are functional and survive after glucocorticoid withdrawal.
• No evidence of acinar-islet or duct-islet cell transformation was observed.