IGF-I augments resection-induced mucosal hyperplasia by altering enterocyte kinetics

Area of Science:

• Gastroenterology
• Regenerative Medicine
• Endocrinology

Background:

• Intestinal resection triggers adaptive growth to compensate for lost absorptive surface.
• Enterocyte kinetics, including proliferation, migration, and apoptosis, are crucial for this adaptation.
• Insulin-like growth factor-I (IGF-I) is a key regulator of cell growth and tissue repair.

Purpose of the Study:

• To investigate if exogenous insulin-like growth factor-I (IGF-I) enhances the adaptive growth response following mid-small bowel resection.
• To assess the impact of IGF-I on enterocyte kinetics (proliferation, apoptosis, migration) during intestinal adaptation.
• To determine IGF-I's role in promoting intestinal tissue regeneration after resection.

Main Methods:

• Growing rats underwent mid-small bowel resection or transection.
• Animals received either exogenous IGF-I or a vehicle control via parenteral feeding.
• Jejunal structural adaptation and enterocyte kinetics were analyzed.

Main Results:

• IGF-I treatment significantly increased jejunal mucosal mass by 20% in resected rats.
• Mucosal protein and DNA concentrations were elevated by 36% and 33%, respectively, with IGF-I.
• IGF-I enhanced enterocyte proliferation and expanded the proliferative crypt compartment, but did not further alter apoptosis or migration.

Conclusions:

• Exogenous IGF-I augments the adaptive growth response to small bowel resection.
• IGF-I acts as an intestinal mitogen, promoting tissue regeneration by enhancing enterocyte proliferation.
• These findings support the therapeutic potential of IGF-I in managing intestinal failure.