engleski

Differences in renal microscopic morphology between wild-type and Tff3 knock-out mice

Introduction Tff3 protein is a mucosal protein involved in protection and restoration of the mucosal barrier, especially in the intestines. It is also found in the kidney and is believed to facilitate the repair of kidney tubular epithelium injury. Tff3 protein expression is also related to some renal pathological conditions, such as renal cancer and chronic kidney disease. Objectives The objectives of this study were to determine effect of Tff3 deficiency on histomorphometric properties of kidney tissue using wild-type mice and Tff3 knock-out mice. Materials & methods Male mice (background C57Bl6/J//Sv129) deficient of Tff3 protein and appropriate wild type mice were used in the study (N=5 each group). Kidneys were harvested, fixed in 4% paraformaldehyde and paraffin-embedded. Blocks with kidney tissue were cut (6 um thick) and slides were stained using PAS method. Digital photographs were taken (5 images of cortex and 3 images of medulla for each animal) and measured using FIJI software. Arithmetic means were obtained for each sample and used for further analysis. Results Tff3 deficient mice have larger total diameter and lumen width of proximal convoluted tubules compared to wild-type mice. Significant difference was not found in other renal histomorphological properties of the examined groups (glomerular cross-sectional area, total diameter and lumen width of distal and collecting ducts, and epithelial height of proximal, distal and collecting ducts). Conclusion Increased diameter of the proximal tubules might point to proximal tubule hypertrophy in Tff3 knock-out mice. In order to confirm this assumption additional studies are needed (possibly including total renal volume measurement, serial kidney sections, studies on mice of different age and studies after pharmacological challenge of kidney function, e.g. using furosemide).

kidney ; renal tubules ; glomerulus ; histology ; Tff3 protein

This research was funded by Croatian Science Foundation grant IP-2016-06-2717. The work of doctoral student Iva Bazina has been fully supported by the “Young researchers career development project – training of doctoral students” of the Croatian Science Foundation funded by the European Union from the European Social Fund. Authors wish to thank Croatian Microscopy Society for supporting this presentation.