In utero undernutrition impairs rat beta-cell development

Area of Science:

• Developmental biology
• Endocrinology
• Nutritional science

Background:

• Maternal nutrition significantly influences fetal development, particularly organogenesis.
• Intrauterine growth restriction (IUGR) is associated with long-term health consequences.
• The endocrine pancreas, responsible for insulin production, is sensitive to nutritional status.

Purpose of the Study:

• To investigate the long-term effects of maternal food restriction on pancreatic beta-cell development in a rat model.
• To assess the impact of intrauterine undernutrition on beta-cell mass, insulin content, and proliferation postnatally.

Main Methods:

• A rat model was established using 50% maternal food restriction from day 15 of pregnancy.
• Offspring (IUGR pups) were compared to controls at postnatal day 1 and day 21.
• Measurements included beta-cell mass, insulin content, islet density, and beta-cell proliferation (BrdU labelling).

Main Results:

• IUGR pups exhibited significantly reduced beta-cell mass and insulin content at postnatal day 1.
• Despite full recovery of body and pancreatic weight by day 21, IUGR animals showed a persistent 40% decrease in beta-cell mass and 25% decrease in insulin content.
• A reduced number of islets was indicated by lower insulin-positive aggregate density in IUGR rats, while beta-cell proliferation remained normal.

Conclusions:

• In utero undernutrition in rats leads to durable impairment of beta-cell development, affecting beta-cell mass and insulin content.
• Postnatal catch-up growth does not fully restore pancreatic endocrine function compromised during gestation.
• The findings suggest a potential impairment in beta-cell differentiation due to prenatal nutritional deficits.