Ileal Transposition (IT) Surgery Changing the Ultrastructure of the Transposed Segment as well as Jejunum. Histomorphometric and Electron Microscopy Analysis

Objective

Ileal transposition (IT) procedure leads to higher secretion of incretin hormones what is associated with a beneficial metabolic effect. However, IT will also have an influence on the related jejunum and ileum function. The aim of this research was to investigate the morphology of the jejunum and transposed ileum with the use of light and transmission electron microscopy (TEM) in order to determine the local alternations in the intestine resulting from the transposition.

Methods

Twenty male, 8-week-old, obese Zucker rats underwent IT and six of them sham surgery. To compare both groups, the transection was made at all corresponding ileum positions among both groups of animals. The ileal anastomoses among the rats of sham procedure were subsequently formed accordingly without IT. Three months following the surgery, the tissue samples of jejunum and ileum were harvested.

Results

A significant increase in villus length, a decrease in the crypt depth, and an increased thickness of mucosa-muscularis-serosa (MMS) as well as cellular hyperplasia, with increased mitochondrial density of the transposed ileum segment, were observed among the group of rats which underwent IT comparing to the ones undergoing sham surgery. In rats undergoing IT, microvillus degeneration in jejunum regions was observed.

Conclusions

Ileal transposition alters the morphology and ultrastructure of the ileum as well as the jejunum. Given that the microvillus membrane represents an important aspect of the enterocyte functions, a further biochemical and molecular research is necessary in order to assess whether the observed changes are beneficial or not and to explore the phenomenon of gut adaptability after metabolic surgery.