Morphometric and functional study of the effect of maternal obesity on rat foetal islet beta cells

ABSTRACT

Maternal obesity during pregnancy was reported to affect the foetal endocrine pancreas. However, a detailed immunohistochemical morphometric structural and functional study on the endocrine pancreas of foetouses of obese mothers was not available. Therefore, the aim of this study was to study the effect of obesity in pregnant rats on the functional and structural integrity of the pancreatic islet beta cells of their foetouses. Pancreatic specimens were obtained from 21 day old foetal rats of obese and non-obese mothers. Sections were stained with indirect immunoperoxidase method to demonstrate beta cells. Sections were also stained with haematoxylin and eosin. A morphometric study was performed on the pancreatic islets. The blood glucose and insulin levels were measured in foetouses of obese and non-obese mothers. The volume density of islets per pancreatic tissue, the volume density of beta cells per islet, the percentage of beta cells per total islet cells and the diameter of foetal pancreatic islets of obese mothers did not vary significantly from that of the controls. The histological structure of foetal pancreatic islets of obese mothers was normal and did not differ from that of the controls. The blood glucose level of foetouses of obese mothers was not significantly different from that of the controls. The blood insulin level of foetouses of obese mothers was significantly higher than that of the controls. The results obtained from this study showed that maternal obesity did not affect the structural integrity of the endocrine pancreatic beta cells or the blood glucose level of foetouses. However, obesity during pregnancy resulted in an increase of foetal blood insulin level